Provided by: pigpio-tools_1.78-1_amd64 bug

NAME

       pigs - command line socket access to the pigpio daemon.

       /dev/pigpio - command line pipe access to the pigpio daemon.

SYNOPSIS

       sudo pigpiod

       then

       pigs {command}+

       or

       echo {command}+ >/dev/pigpio

DESCRIPTION

       The socket and pipe interfaces allow control of the Pi's GPIO by passing messages to the
       running pigpio library.

       The normal way to start the pigpio library would be as a daemon during boot.

       sudo pigpiod

   Features
       o hardware timed PWM on any of GPIO 0-31

       o hardware timed servo pulses on any of GPIO 0-31

       o reading/writing all of the GPIO in a bank as one operation

       o individually setting GPIO modes, reading and writing

       o notifications when any of GPIO 0-31 change state

       o the construction of output waveforms with microsecond timing

       o I2C, SPI, and serial link wrappers

       o creating and running scripts on the pigpio daemon

   GPIO
       ALL GPIO are identified by their Broadcom number.

   Usage
       pigs is a program and internally uses the socket interface to pigpio whereas /dev/pigpio
       uses the pipe interface.

       pigs and the pipe interface share the same commands and are invoked in a similar fashion
       from the command line.

       The pigpio library must be running, either by running a program linked with the library or
       starting the pigpio daemon (sudo pigpiod).

       pigs {command}+

       echo "{command}+" >/dev/pigpio

       pigs will show the result of the command on screen.

       The pigs process returns an exit status (which can be displayed with the command echo $?).

       PIGS_OK            0
       PIGS_CONNECT_ERR 255
       PIGS_OPTION_ERR  254
       PIGS_SCRIPT_ERR  253

       The results of /dev/pigpio commands need to be read from /dev/pigout, e.g. cat /dev/pigout
       (try cat /dev/pigout& so that all subsequent results are shown on screen).

       In both cases if an error was detected a message will have been written to /dev/pigerr
       (try cat /dev/pigerr&).  This is likely to be more informative than the message returned
       by pigs or the error code returned by the pipe interface.

       Several commands may be entered on a line.  If present PROC and PARSE must be the last
       command on a line.

       E.g.

       pigs w 22 1 mils 1000 w 22 0

       is equivalent to

       pigs w 22 1
       pigs mils 1000
       pigs w 22 0

       and

       echo "m 4 w w 4 0 mils 250 m 4 r r 4" >/dev/pigpio

       is equivalent to

       echo "m 4 w"    >/dev/pigpio
       echo "w 4 0"    >/dev/pigpio
       echo "mils 250" >/dev/pigpio
       echo "m 4 r"    >/dev/pigpio
       echo "r 4"      >/dev/pigpio

   Notes
       The examples from now on will show the pigs interface but the same commands will also work
       on the pipe interface.

       pigs does not show the status of successful commands unless the command itself returns
       data.  The status (0) will be returned to pigs but will be discarded.

       The status/data of each command sent to the pipe interface should be read from
       /dev/pigout.

       When a command takes a number as a parameter it may be entered as hex (precede by 0x),
       octal (precede by 0), or decimal.

       E.g. 23 is 23 decimal, 0x100 is 256 decimal, 070 is 56 decimal.

       Some commands can return a variable number of data bytes.  By default this data is
       displayed as decimal.  The pigs -a option can be used to force the display as ASCII and
       the pigs -x option can be used to force the display as hex.

       E.g. assuming the transmitted serial data is the letters ABCDEONM

       $ pigs slr 4 100
       8 65 66 67 68 69 79 78 77

       $ pigs -a slr 4 100
       8 ABCDEONM

       $ pigs -x slr 4 100
       8 41 42 43 44 45 4f 4e 4d

OVERVIEW

   BASIC
       M/MODES g m Set GPIO mode

       MG/MODEG g Get GPIO mode

       PUD g p Set GPIO pull up/down

       R/READ g Read GPIO level

       W/WRITE g L Write GPIO level

   PWM (overrides servo commands on same GPIO)
       P/PWM u v Set GPIO PWM value

       PFS u v Set GPIO PWM frequency

       PRS u v Set GPIO PWM range

       GDC u Get GPIO PWM dutycycle

       PFG u Get GPIO PWM frequency

       PRG u Get GPIO PWM range

       PRRG u Get GPIO PWM real range

   Servo (overrides PWM commands on same GPIO)
       S/SERVO u v Set GPIO servo pulsewidth

       GPW u Get GPIO servo pulsewidth

   INTERMEDIATE
       TRIG u pl L Send a trigger pulse

       WDOG u v Set GPIO watchdog

       BR1 Read bank 1 GPIO

       BR2 Read bank 2 GPIO

       BC1 bits Clear specified GPIO in bank 1

       BC2 bits Clear specified GPIO in bank 2

       BS1 bits Set specified GPIO in bank 1

       BS2 bits Set specified GPIO in bank 2

   ADVANCED
       NO Request a notification

       NC h Close notification

       NB h bits Start notification

       NP h Pause notification

       HC g cf Set hardware clock frequency

       HP g pf pdc Set hardware PWM frequency and dutycycle

       FG u stdy Set a glitch filter on a GPIO

       FN u stdy actv Set a noise filter on a GPIO

       PADS pad padma Set pad drive strength

       PADG pad Get pad drive strength

       SHELL name str Execute a shell command

   Custom
       CF1 uvs Custom function 1

       CF2 uvs Custom function 2

   Events
       EVM h bits Set events to monitor

       EVT event Trigger event

   Scripts
       PROC t Store script

       PROCR sid pars Run script

       PROCU sid pars Set script parameters

       PROCP sid Get script status and parameters

       PROCS sid Stop script

       PROCD sid Delete script

       PARSE t Validate script

   I2C
       I2CO ib id if Open I2C bus and device with flags

       I2CC h Close I2C handle

       I2CWQ h bit smb Write Quick: write bit

       I2CRS h smb Read Byte: read byte

       I2CWS h bv smb Write Byte: write byte

       I2CRB h r smb Read Byte Data: read byte from register

       I2CWB h r bv smb Write Byte Data: write byte to register

       I2CRW h r smb Read Word Data: read word from register

       I2CWW h r wv smb Write Word Data: write word to register

       I2CRK h r smb Read Block Data: read data from register

       I2CWK h r bvs smb Write Block Data: write data to register

       I2CWI h r bvs smb Write I2C Block Data

       I2CRI h r num smb Read I2C Block Data: read bytes from register

       I2CRD h num i2c Read device

       I2CWD h bvs i2c Write device

       I2CPC h r wv smb Process Call: exchange register with word

       I2CPK h r bvs smb Block Process Call: exchange data bytes with register

       I2CZ h bvs Performs multiple I2C transactions

   I2C BIT BANG
       BI2CO sda scl b Open bit bang I2C

       BI2CC sda Close bit bang I2C

       BI2CZ sda bvs I2C bit bang multiple transactions

   I2C/SPI SLAVE
       BSCX bctl bvs BSC I2C/SPI transfer

   SERIAL
       SERO dev b sef Open serial device dev at baud b with flags

       SERC h Close serial handle

       SERRB Read byte from serial handle

       SERWB h bv Write byte to serial handle

       SERR h num Read bytes from serial handle

       SERW h bvs Write bytes to serial handle

       SERDA h Check for serial data ready to read

   SERIAL BIT BANG (read only)
       SLRO u b db Open GPIO for bit bang serial data

       SLRC u Close GPIO for bit bang serial data

       SLRI u v Sets bit bang serial data logic levels

       SLR u num Read bit bang serial data from GPIO

   SPI
       SPIO c b spf SPI open channel at baud b with flags

       SPIC h SPI close handle

       SPIR h num SPI read bytes from handle

       SPIW h bvs SPI write bytes to handle

       SPIX h bvs SPI transfer bytes to handle

   SPI BIT BANG
       BSPIO cs miso mosi sclk b spf Open bit bang SPI

       BSPIC cs Close bit bang SPI

       BSPIX cs bvs SPI bit bang transfer

   FILES
       FO file mode Open a file in mode

       FC h Close file handle

       FR h num Read bytes from file handle

       FW h bvs Write bytes to file handle

       FS h num from Seek to file handle position

       FL pat num List files which match pattern

   WAVES
       WVCLR Clear all waveforms

       WVNEW Initialise a new waveform

       WVAG trips Add generic pulses to waveform

       WVAS u b db sb o bvs Add serial data to waveform

       WVCRE Create a waveform

       WVCAP percent Create a waveform of fixed size

       WVDEL wid Delete selected waveform

       WVTX wid Transmits waveform once

       WVTXM wid wmde Transmits waveform using mode

       WVTXR wid Transmits waveform repeatedly

       WVCHA bvs Transmits a chain of waveforms

       WVTAT Returns the current transmitting waveform

       WVBSY Check if waveform is being transmitted

       WVHLT Stop waveform

       WVSC ws Get waveform DMA CB stats

       WVSM ws Get waveform time stats

       WVSP ws Get waveform pulse stats

   UTILITIES
       H/HELP Display command help

       HWVER Get hardware version

       MICS v Microseconds delay

       MILS v Milliseconds delay

       PIGPV Get pigpio library version

       T/TICK Get current tick

   CONFIGURATION
       CGI Configuration get internals

       CSI v Configuration set internals

COMMANDS

       BC1 bits - Clear specified GPIO in bank 1

           This command clears (sets low) the GPIO specified by bits in bank 1.  Bank 1 consists
           of GPIO 0-31.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs bc1 0x400010 # clear GPIO 4 (1<<4) and 22 (1<<22)

           $ pigs bc1 32 # clear GPIO 5 (1<<5)
           -42
           ERROR: no permission to update one or more GPIO

       BC2 bits - Clear specified GPIO in bank 2

           This command clears (sets low) the GPIO specified by bits in bank 2.  Bank 2 consists
           of GPIO 32-53.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs bc2 0x8000 # clear GPIO 47 (activity LED on A+/B+/Pi2/Pi3)

           $ pigs bc2 1 # clear GPIO 32 (first in bank 2)
           -42
           ERROR: no permission to update one or more GPIO

       BI2CC sda - Close bit bang I2C

           This command signals that bit banging I2C on sda (and scl) is no longer required.

           Example

           $ pigs bi2cc 5

       BI2CO sda scl b - Open bit bang I2C

           This command signals that GPIO sda and scl are to be used for bit banging I2C at b
           baud.

           Bit banging I2C allows for certain operations which are not possible with the standard
           I2C driver.

           o baud rates as low as 50
           o repeated starts
           o clock stretching
           o I2C on any pair of spare GPIO

           The baud rate may be between 50 and 500000 bits per second.

           The GPIO used for SDA and SCL must have pull-ups to 3V3 connected.  As a guide the
           hardware pull-ups on pins 3 and 5 are 1k8 in value.

       BI2CZ sda bvs - I2C bit bang multiple transactions

           This function executes a sequence of bit banged I2C operations.  The operations to be
           performed are specified by the contents of bvs which contains the concatenated command
           codes and associated data.

           The following command codes are supported:

           Name      Cmd & Data     Meaning
           End       0              No more commands
           Escape    1              Next P is two bytes
           Start     2              Start condition
           Stop      3              Stop condition
           Address   4 P            Set I2C address to P
           Flags     5 lsb msb      Set I2C flags to lsb + (msb << 8)
           Read      6 P            Read P bytes of data
           Write     7 P ...        Write P bytes of data

           The address, read, and write commands take a parameter P.  Normally P is one byte
           (0-255).  If the command is preceded by the Escape command then P is two bytes
           (0-65535, least significant byte first).

           The address and flags default to 0.  The address and flags maintain their previous
           value until updated.

           No flags are currently defined.

           Example

           Set address 0x53
           start, write 0x32, (re)start, read 6 bytes, stop
           Set address 0x1E
           start, write 0x03, (re)start, read 6 bytes, stop
           Set address 0x68
           start, write 0x1B, (re)start, read 8 bytes, stop
           End

           0x04 0x53
           0x02 0x07 0x01 0x32   0x02 0x06 0x06 0x03

           0x04 0x1E
           0x02 0x07 0x01 0x03   0x02 0x06 0x06 0x03

           0x04 0x68
           0x02 0x07 0x01 0x1B   0x02 0x06 0x08 0x03

           0x00

       BR1  - Read bank 1 GPIO

           This command read GPIO 0-31 (bank 1) and returns the levels as a 32-bit hexadecimal
           value.

           Example

           $ pigs br1
           1001C1CF

       BR2  - Read bank 2 GPIO

           This command read GPIO 32-53 (bank 2) and returns the levels as a 32-bit hexadecimal
           value.

           Example

           $ pigs br2
           003F0000

       BS1 bits - Set specified GPIO in bank 1

           This command sets (sets high) the GPIO specified by bits in bank 1.  Bank 1 consists
           of GPIO 0-31.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs bs1 16 # set GPIO 4 (1<<4)

           $ pigs bs1 1 # set GPIO 1 (1<<0)
           -42
           ERROR: no permission to update one or more GPIO

       BS2 bits - Set specified GPIO in bank 2

           This command sets (sets high) the GPIO specified by bits in bank 2.  Bank 2 consists
           of GPIO 32-53.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs bs2 0x40 # set GPIO 38 (enable high current mode A+/B+/Pi2/Pi3)

           $ pigs bs2 1 # set GPIO 32 (first in bank 2)
           -42
           ERROR: no permission to update one or more GPIO

       BSCX bctl bvs - BSC I2C/SPI transfer

           This command performs a BSC I2C/SPI slave transfer as defined by bctl with data bvs.

           This function provides a low-level interface to the SPI/I2C Slave peripheral on the
           BCM chip.

           This peripheral allows the Pi to act as a hardware slave device on an I2C or SPI bus.

           This is not a bit bang version and as such is OS timing independent. The bus timing is
           handled directly by the chip.

           The output process is simple. You simply append data to the FIFO buffer on the chip.
           This works like a queue, you add data to the queue and the master removes it.

           I can't get SPI to work properly.  I tried with a control word of 0x303 and swapped
           MISO and MOSI.

           The command sets the BSC mode and writes any data bvs to the BSC transmit FIFO.  It
           returns the data count (at least 1 for the status word), the status word, followed by
           any data bytes read from the BSC receive FIFO.

           Note that the control word sets the BSC mode.  The BSC will stay in that mode until a
           different control word is sent.

           For I2C use a control word of (I2C address << 16) + 0x305.

           E.g. to talk as I2C slave with address 0x13 use 0x130305.

           GPIO used for models other than those based on the BCM2711.

                 SDA   SCL   MOSI   SCLK   MISO   CE
           I2C   18    19    -      -      -      -
           SPI   -     -     18     19     20     21

           GPIO used for models based on the BCM2711 (e.g. the Pi4B).

                 SDA   SCL   MOSI   SCLK   MISO   CE
           I2C   10    11    -      -      -      -
           SPI   -     -     10     11     9      8

           When a zero control word is received the used GPIO will be reset to INPUT mode.

           The control word consists of the following bits.

           22 21 20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            a  a  a  a  a  a  a  -  - IT HC TF IR RE TE BK EC ES PL PH I2 SP EN

           Bits 0-13 are copied unchanged to the BSC CR register.  See pages 163-165 of the
           Broadcom peripherals document for full details.

           aaaaaaa   defines the I2C slave address (only relevant in I2C mode)
           IT        invert transmit status flags
           HC        enable host control
           TF        enable test FIFO
           IR        invert receive status flags
           RE        enable receive
           TE        enable transmit
           BK        abort operation and clear FIFOs
           EC        send control register as first I2C byte
           ES        send status register as first I2C byte
           PL        set SPI polarity high
           PH        set SPI phase high
           I2        enable I2C mode
           SP        enable SPI mode
           EN        enable BSC peripheral

           The returned status has the following format

           20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            S  S  S  S  S  R  R  R  R  R  T  T  T  T  T RB TE RF TF RE TB

           Bits 0-15 are copied unchanged from the BSC FR register.  See pages 165-166 of the
           Broadcom peripherals document for full details.

           SSSSS   number of bytes successfully copied to transmit FIFO
           RRRRR   number of bytes in receieve FIFO
           TTTTT   number of bytes in transmit FIFO
           RB      receive busy
           TE      transmit FIFO empty
           RF      receive FIFO full
           TF      transmit FIFO full
           RE      receive FIFO empty
           TB      transmit busy

           This example assumes that GPIO 2/3 are connected to GPIO 18/19 (GPIO 10/11 on the
           BCM2711).

           Example

           $ pigs bscx 0x130305 # start BSC as I2C slave 0x13
           1 18

           $ i2cdetect -y 1
                0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
           00:          -- -- -- -- -- -- -- -- -- -- -- -- --
           10: -- -- -- 13 -- -- -- -- -- -- -- -- -- -- -- --
           20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
           30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
           40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
           50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
           60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
           70: -- -- -- -- -- -- -- --

           $ pigs i2co 1 0x13 0 # get handle for device 0x13 on bus 1
           0

           $ pigs i2cwd 0 90 87 51 9 23 # write 5 bytes

           $ pigs bscx 0x130305 # check for data
           6 18 90 87 51 9 23

           $ pigs bscx 0x130305 11 13 15 17 # check for data and send 4 bytes
           1 262338

           $ pigs i2crd 0 4 # read 4 bytes
           4 11 13 15 17

           $ pigs i2cwd 0 90 87 51 9 23 # write 5 bytes
           $ pigs bscx 0x130305 11 13 15 17 # check for data and send 4 bytes
           6 262338 90 87 51 9 23

           $ pigs i2crd 0 4
           4 11 13 15 17

           $ pigs bscx 0x130305 22 33 44 55 66
           1 327938
           $ pigs i2crd 0 5
           5 22 33 44 55 66

       BSPIC cs - Close bit bang SPI

           This command stops bit banging SPI on a set of GPIO opened with BSPIO.

           The set of GPIO is specifed by cs.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs bspic 10

           $ pigs bspic 10
           -142
           ERROR: no bit bang SPI in progress on GPIO

       BSPIO cs miso mosi sclk b spf - Open bit bang SPI

           This command starts bit banging SPI on a group of GPIO with slave select cs, MISO
           miso, MOSI mosi, and clock sclk.

           Data will be transferred at baud b bits per second (which may be set in the range
           50-250000).

           The flags spf may be used to modify the default behaviour of mode 0, active low chip
           select.

           The flags consists of the least significant 22 bits.

           21 20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            0  0  0  0  0  0  R  T  0  0  0  0  0  0  0  0  0  0  0  p  m  m

           mm defines the SPI mode.

           Mode POL PHA
            0    0   0
            1    0   1
            2    1   0
            3    1   1

           p is 0 if CS is active low (default) and 1 for active high.

           T is 1 if the least significant bit is transmitted on MOSI first, the default (0)
           shifts the most significant bit out first.

           R is 1 if the least significant bit is received on MISO first, the default (0)
           receives the most significant bit first.

           The other bits in flags should be set to zero.

           Upon success 0 is returned.  On error a negative status code will be returned.

           If more than one device is connected to the SPI bus (defined by SCLK, MOSI, and MISO)
           each must have its own CS.

           Example

           $ pigs bspio  9 11 12 13 50000 0

           $ pigs bspio 10 11 12 13 50000 0

           $ pigs bspio 29 19 20 21 50000 0 # GPIO 29 not avaialble on this Pi
           -41
           ERROR: no permission to update GPIO

       BSPIX cs bvs - SPI bit bang transfer

           This command writes bytes bvs to the bit bang SPI device associated with slave select
           cs.  It returns the same number of bytes read from the device.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs bspio 5 13 19 12 10000 0 # MCP4251 DAC
           $ pigs bspio 6 13 19 12 20000 3 # MCP3008 ADC

           $ pigs bspix 5 0 16             # set DAC to 16
           2 255 255

           $ pigs bspix 5 12 0             # read back DAC
           2 254 16

           $ pigs bspix 6 1 128 0          # read ADC input 0
           3 0 3 184                       # 952

           $ pigs bspix 5 0 240            # set DAC to 240
           2 255 255

           $ pigs bspix 5 12 0             # read back DAC
           2 254 240

           $ pigs bspix 6 1 128 0          # read ADC input 0
           3 0 0 63                        # 63

           $ pigs bspix 5 0 128            # set DAC to 128
           2 255 255

           $ pigs bspix 5 12 0             # read back DAC
           2 254 128

           $ pigs bspix 6 1 128 0          # read ADC input 0
           3 0 1 255                       # 511

           $ pigs bspic 5                  # close SPI CS 5
           $ pigs bspic 6                  # close SPI CS 6

           $ pigs bspic 5                  # try to close SPI CS 5 again
           -142
           ERROR: no bit bang SPI in progress on GPIO

       CF1 uvs - Custom function 1

           This command calls a user customised function.  The meaning of any paramaters and the
           returned value is defined by the customiser.

       CF2 uvs - Custom function 2

           This command calls a user customised function.  The meaning of any paramaters and the
           returned value is defined by the customiser.

       CGI  - Configuration get internals

           This command returns the value of the internal library configuration settings.

       CSI v - Configuration set internals

           This command sets the value of the internal library configuration settings to v.

       EVM h bits - Set events to monitor

           This command starts event reporting on handle h (returned by a prior call to NO).

           Upon success nothing is returned.  On error a negative status code will be returned.

           The notification gets reports for each event specified by bits.

           Example

           $ pigs evm 0 -1 # Shorthand for events 0-31.
           $ pigs evm 0 0xf0 # Get notifications for events 4-7.

           $ pigs evm 1 0xf
           -25
           ERROR: unknown handle

       EVT event - Trigger event

           This command triggers event event.

           One event, number 31, is predefined.  This event is auto generated on BSC slave
           activity.

           Example

           $ pigs evt 12
           $ pigs evt 5

           $ pigs evt 32
           -143
           ERROR: bad event id

       FC h - Close file handle

           This command closes a file handle h previously opened with FO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs fc 0 # First close okay.

           $ pigs fc 0 # Second fails.
           -25
           ERROR: unknown handle

       FG u stdy - Set a glitch filter on a GPIO

           Level changes on the GPIO u are not reported unless the level has been stable for at
           least stdy microseconds.  The level is then reported.  Level changes of less than stdy
           microseconds are ignored.

           The filter only affects callbacks (including pipe notifications).

           The R/READ, BR1, and BR2 commands are not affected.

           Note, each (stable) edge will be timestamped stdy microseconds after it was first
           detected.

           Example

           $ pigs fg 4 250

           $ pigs fg 4 1000000
           -125
           ERROR: bad filter parameter

       FL pat num - List files which match pattern

           This command returns a list of the files matching pat. Up to num bytes may be
           returned.

           Upon success the count of returned bytes followed by the matching files is returned.
           On error a negative status code will be returned.

           A newline (0x0a) character separates each file name.

           Only files which have a matching entry in /opt/pigpio/access may be listed.

           Suppose /opt/pigpio/access contains

           /sys/bus/w1/devices/28*/w1_slave r

           Example

           $ pigs -a fl "/sys/bus/w1/devices/28*/w1_slave" 5000
           90 /sys/bus/w1/devices/28-000005d34cd2/w1_slave
           /sys/bus/w1/devices/28-001414abbeff/w1_slave

           $ pigs -a fl "/sys/bus/*" 5000
           ERROR: no permission to access file
           -137

       FN u stdy actv - Set a noise filter on a GPIO

           Level changes on the GPIO u are ignored until a level which has been stable for stdy
           microseconds is detected.  Level changes on the GPIO are then reported for actv
           microseconds after which the process repeats.

           The filter only affects callbacks (including pipe notifications).

           The R/READ, BR1, and BR2 commands are not affected.

           Note, level changes before and after the active period may be reported.  Your software
           must be designed to cope with such reports.

           Example

           $ pigs fn 7 250 1000

           $ pigs fn 7 2500000 1000
           -125
           ERROR: bad filter parameter

       FO file mode - Open a file in mode

           This function returns a handle to a file file opened in a specified mode mode.

           Upon success a handle (>=0) is returned.  On error a negative status code will be
           returned.

           File

           A file may only be opened if permission is granted by an entry in /opt/pigpio/access.
           This is intended to allow remote access to files in a more or less controlled manner.

           Each entry in /opt/pigpio/access takes the form of a file path which may contain
           wildcards followed by a single letter permission.  The permission may be R for read, W
           for write, U for read/write, and N for no access.

           Where more than one entry matches a file the most specific rule applies.  If no entry
           matches a file then access is denied.

           Suppose /opt/pigpio/access contains the following entries

           /home/* n
           /home/pi/shared/dir_1/* w
           /home/pi/shared/dir_2/* r
           /home/pi/shared/dir_3/* u
           /home/pi/shared/dir_1/file.txt n

           Files may be written in directory dir_1 with the exception of file.txt.

           Files may be read in directory dir_2.

           Files may be read and written in directory dir_3.

           If a directory allows read, write, or read/write access then files may be created in
           that directory.

           In an attempt to prevent risky permissions the following paths are ignored in
           /opt/pigpio/access.

           a path containing ..
           a path containing only wildcards (*?)
           a path containing less than two non-wildcard parts

           Mode

           The mode may have the following values.

                   Value   Meaning
           READ      1     open file for reading
           WRITE     2     open file for writing
           RW        3     open file for reading and writing

           The following values may be or'd into the mode.

                    Value   Meaning
           APPEND     4     All writes append data to the end of the file
           CREATE     8     The file is created if it doesn't exist
           TRUNC     16     The file is truncated

           Newly created files are owned by root with permissions owner read and write.

           Example

           $ ls /ram/*.c
           /ram/command.c      /ram/pigpiod.c  /ram/pigs.c
           /ram/x_pigpiod_if.c /ram/pig2vcd.c  /ram/pigpiod_if2.c
           /ram/x_pigpio.c     /ram/x_repeat.c /ram/pigpio.c
           /ram/pigpiod_if.c   /ram/x_pigpiod_if2.c

           # assumes /opt/pigpio/access contains the following line
           # /ram/*.c r

           $ pigs fo /ram/pigpio.c 1
           0

           $ pigs fo /ram/new.c 1
           -128
           ERROR: file open failed

           $ pigs fo /ram/new.c 9
           1

           $ ls /ram/*.c -l
           -rw-r--r-- 1 joan joan  42923 Jul 10 11:22 /ram/command.c
           -rw------- 1 root root      0 Jul 10 16:54 /ram/new.c
           -rw-r--r-- 1 joan joan   2971 Jul 10 11:22 /ram/pig2vcd.c
           -rw------- 1 joan joan 296235 Jul 10 11:22 /ram/pigpio.c
           -rw-r--r-- 1 joan joan   9266 Jul 10 11:22 /ram/pigpiod.c
           -rw-r--r-- 1 joan joan  37331 Jul 10 11:22 /ram/pigpiod_if2.c
           -rw-r--r-- 1 joan joan  33088 Jul 10 11:22 /ram/pigpiod_if.c
           -rw-r--r-- 1 joan joan   7990 Jul 10 11:22 /ram/pigs.c
           -rw-r--r-- 1 joan joan  19970 Jul 10 11:22 /ram/x_pigpio.c
           -rw-r--r-- 1 joan joan  20804 Jul 10 11:22 /ram/x_pigpiod_if2.c
           -rw-r--r-- 1 joan joan  19844 Jul 10 11:22 /ram/x_pigpiod_if.c
           -rw-r--r-- 1 joan joan  19907 Jul 10 11:22 /ram/x_repeat.c

       FR h num - Read bytes from file handle

           This command returns up to num bytes of data read from the file associated with handle
           h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs fr 0 10
           5 48 49 128 144 255

           $ pigs fr 0 10
           0

       FS h num from - Seek to file handle position

           This command seeks to a position within the file associated with handle h.

           The number of bytes to move is num.  Positive offsets move forward, negative offsets
           backwards.  The move start position is determined by from as follows.

               From
           0   start
           1   current position
           2   end

           Upon success the new byte position within the file (>=0) is returned.  On error a
           negative status code will be returned.

           Example

           $ pigs fs 0 200 0 # Seek to start of file plus 200
           200

           $ pigs fs 0 0 1 # Return current position
           200

           $ pigs fs 0 0 2 # Seek to end of file, return size
           296235

       FW h bvs - Write bytes to file handle

           This command writes bytes bvs to the file associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs fw 0 23 45 67 89

       GDC u - Get GPIO PWM dutycycle

           This command returns the PWM dutycycle in use on GPIO u.

           Upon success the dutycycle is returned.  On error a negative status code will be
           returned.

           For normal PWM the dutycycle will be out of the defined range for the GPIO (see PRG).

           If a hardware clock is active on the GPIO the reported dutycycle will be 500000 (500k)
           out of 1000000 (1M).

           If hardware PWM is active on the GPIO the reported dutycycle will be out of a 1000000
           (1M).

           Example

           $ pigs p 4 129
           $ pigs gdc 4
           129

           pigs gdc 5
           -92
           ERROR: GPIO is not in use for PWM

       GPW u - Get GPIO servo pulsewidth

           This command returns the servo pulsewidth in use on GPIO u.

           Upon success the servo pulsewidth is returned.  On error a negative status code will
           be returned.

           Example

           $ pigs s 4 1235
           $ pigs gpw 4
           1235

           $ pigs gpw 9
           -93
           ERROR: GPIO is not in use for servo pulses

       H/HELP  - Display command help

           This command displays a brief list of the commands and their parameters.

           Example

           $ pigs h

           $ pigs help

       HC g cf - Set hardware clock frequency

           This command sets the hardware clock associated with GPIO g to frequency cf.
           Frequencies above 30MHz are unlikely to work.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs hc 4 5000 # start a 5 KHz clock on GPIO 4 (clock 0)

           $ pigs hc 5 5000000 # start a 5 MHz clcok on GPIO 5 (clock 1)
           -99
           ERROR: need password to use hardware clock 1

           The same clock is available on multiple GPIO.  The latest frequency setting will be
           used by all GPIO which share a clock.

           The GPIO must be one of the following.

           4   clock 0  All models
           5   clock 1  All models but A and B (reserved for system use)
           6   clock 2  All models but A and B
           20  clock 0  All models but A and B
           21  clock 1  All models but A and B Rev.2 (reserved for system use)

           32  clock 0  Compute module only
           34  clock 0  Compute module only
           42  clock 1  Compute module only (reserved for system use)
           43  clock 2  Compute module only
           44  clock 1  Compute module only (reserved for system use)

           Access to clock 1 is protected by a password as its use will likely crash the Pi.  The
           password is given by or'ing 0x5A000000 with the GPIO number.

       HP g pf pdc - Set hardware PWM frequency and dutycycle

           This command sets the hardware PWM associated with GPIO g to frequency pf with
           dutycycle pdc. Frequencies above 30MHz are unlikely to work.

           NOTE: Any waveform started by WVTX, WVTXR, or WVCHA will be cancelled.

           This function is only valid if the pigpio main clock is PCM.  The main clock defaults
           to PCM but may be overridden when the pigpio daemon is started (option -t).

           Upon success nothing is returned.  On error a negative status code will be returned.

           $ pigs hp 18 100 800000 # 80% dutycycle

           $ pigs hp 19 100 200000 # 20% dutycycle

           $ pigs hp 19 400000000 100000
           -96
           ERROR: invalid hardware PWM frequency

           The same PWM channel is available on multiple GPIO.  The latest frequency and
           dutycycle setting will be used by all GPIO which share a PWM channel.

           The GPIO must be one of the following.

           12  PWM channel 0  All models but A and B
           13  PWM channel 1  All models but A and B
           18  PWM channel 0  All models
           19  PWM channel 1  All models but A and B

           40  PWM channel 0  Compute module only
           41  PWM channel 1  Compute module only
           45  PWM channel 1  Compute module only
           52  PWM channel 0  Compute module only
           53  PWM channel 1  Compute module only

           The actual number of steps beween off and fully on is the integral part of 250M/pf
           (375M/pf for the BCM2711).

           The actual frequency set is 250M/steps (375M/steps for the BCM2711).

           There will only be a million steps for a pf of 250 (375 for the BCM2711). Lower
           frequencies will have more steps and higher frequencies will have fewer steps.  pdc is
           automatically scaled to take this into account.

       HWVER  - Get hardware version

           This command returns the hardware revision of the Pi.

           The hardware revision is found in the last 4 characters on the revision line of
           /proc/cpuinfo.

           If the hardware revision can not be found or is not a valid hexadecimal number the
           command returns 0.

           The revision number can be used to determine the assignment of GPIO to pins (see g).

           There are currently three types of board.

           Type 1 boards have hardware revision numbers of 2 and 3.

           Type 2 boards have hardware revision numbers of 4, 5, 6, and 15.

           Type 3 boards have hardware revision numbers of 16 or greater.

           for "Revision : 0002" the command returns 2.

           for "Revision : 000f" the command returns 15.

           for "Revision : 000g" the command returns 0.

           Example

           $ pigs hwver # On a B+
           16

       I2CC h - Close I2C handle

           This command closes an I2C handle h previously opened with I2CO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cc 0 # First close okay.

           $ pigs i2cc 0 # Second fails.
           -25
           ERROR: unknown handle

       I2CO ib id if - Open I2C bus and device with flags

           This command returns a handle to access device id on I2C bus ib.  The device is opened
           with flags if.

           Physically buses 0 and 1 are available on the Pi.  Higher numbered buses will be
           available if a kernel supported bus multiplexor is being used.

           The GPIO used are given in the following table.

                   SDA   SCL
           I2C 0    0     1
           I2C 1    2     3

           No flags are currently defined.  The parameter if should be 0.

           Upon success the next free handle (>=0) is returned.  On error a negative status code
           will be returned.

           Example

           $ pigs i2co 1 0x70 0 # Bus 1, device 0x70, flags 0.
           0

           $ pigs i2co 1 0x53 0 # Bus 1, device 0x53, flags 0.
           1

       I2CPC h r wv - smb Process Call: exchange register with word

           This command writes wv to register r of the I2C device associated with handle h and
           returns a 16-bit word read from the device.

           Upon success a value between 0 and 65535 will be returned.  On error a negative status
           code will be returned.

           Example

           $ pigs i2cpc 0 37 43210
           39933

           $ pigs i2cpc 0 256 43210
           ERROR: bad i2c/spi/ser parameter
           -81

       I2CPK h r bvs - smb Block Process Call: exchange data bytes with register

           This command writes the data bytes bvs to register r of the I2C device associated with
           handle h and returns a device specific number of bytes.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs i2cpk 0 0 0x11 0x12
           6 0 0 0 0 0 0

       I2CRB h r - smb Read Byte Data: read byte from register

           This command returns a single byte read from register r of the I2C device associated
           with handle h.

           Upon success a value between 0 and 255 will be returned.  On error a negative status
           code will be returned.

           Example

           $ pigs i2crb 0 0
           6

       I2CRD h num - i2c Read device

           This command returns num bytes read from the I2C device associated with handle h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           This command operates on the raw I2C device.  The maximum value of the parameter num
           is dependent on the I2C drivers and the device itself. pigs imposes a limit of about
           8000 bytes.

           Example

           $ pigs i2crd 0 16
           16 6 24 0 0 0 0 0 0 0 0 0 0 0 0 32 78

       I2CRI h r num - smb Read I2C Block Data: read bytes from register

           This command returns num bytes from register r of the I2C device associated with
           handle h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           The parameter num may be 1-32.

           Example

           $ pigs i2cri 0 0 16
           16 237 155 155 155 155 155 155 155 155 155 155 155 155 155 155 155

       I2CRK h r - smb Read Block Data: read data from register

           This command returns between 1 and 32 bytes read from register r of the I2C device
           associated with handle h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           The number of bytes of returned data is specific to the device and register.

           Example

           $ pigs i2crk 0 0
           6 0 0 0 0 0 0

           $ pigs i2crk 0 1
           24 0 0 0 0 0 0 0 0 0 0 0 0 120 222 105 215 128 87 195 217 0 0 0 0

       I2CRS h - smb Read Byte: read byte

           This command returns a single byte read from the I2C device associated with handle h.

           Upon success a value between 0 and 255 will be returned.  On error a negative status
           code will be returned.

           Example

           $ pigs i2crs 0
           0

       I2CRW h r - smb Read Word Data: read word from register

           This command returns a single 16 bit word read from register r of the I2C device
           associated with handle h.

           Upon success a value between 0 and 65535 will be returned.  On error a negative status
           code will be returned.

           Example

           $ pigs i2crw 0 0
           6150

       I2CWB h r bv - smb Write Byte Data: write byte to register

           This command writes a single byte bv to register r of the I2C device associated with
           handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cwb 0 10 0x54

       I2CWD h bvs - i2c Write device

           This command writes a block of bytes bvs to the I2C device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The number of bytes which may be written in one transaction is dependent on the I2C
           drivers and the device itself.  pigs imposes a limit of about 500 bytes.

           This command operates on the raw I2C device.

           Example

           $ pigs i2cwd 0 0x01 0x02 0x03 0x04

       I2CWI h r bvs - smb Write I2C Block Data

           This command writes between 1 and 32 bytes bvs to register r of the I2C device
           associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cwi 0 4 0x01 0x04 0xc0

       I2CWK h r bvs - smb Write Block Data: write data to register

           This command writes between 1 and 32 bytes bvs to register r of the I2C device
           associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           pigs i2cwk 0 4 0x01 0x04 0xc0

       I2CWQ h bit - smb Write Quick: write bit

           This command writes a single bit to the I2C device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cwq 0 1

       I2CWS h bv - smb Write Byte: write byte

           This command writes a single byte bv to the I2C device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cws 0 0x12

           $ pigs i2cws 0 0xff
           -82
           ERROR: I2C write failed

       I2CWW h r wv - smb Write Word Data: write word to register

           This command writes a single 16 bit word wv to register r of the I2C device associated
           with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs i2cww 0 0 0xffff

       I2CZ h bvs - Performs multiple I2C transactions

           This command executes a sequence of I2C operations.  The operations to be performed
           are specified by the contents of bvs which contains the concatenated command codes and
           associated data.

           The following command codes are supported:

           Name      Cmd & Data   Meaning
           End       0            No more commands
           Escape    1            Next P is two bytes
           On        2            Switch combined flag on
           Off       3            Switch combined flag off
           Address   4 P          Set I2C address to P
           Flags     5 lsb msb    Set I2C flags to lsb + (msb << 8)
           Read      6 P          Read P bytes of data
           Write     7 P ...      Write P bytes of data

           The address, read, and write commands take a parameter P.  Normally P is one byte
           (0-255).  If the command is preceded by the Escape command then P is two bytes
           (0-65535, least significant byte first).

           The address defaults to that associated with the handle h.  The flags default to 0.
           The address and flags maintain their previous value until updated.

           Example

           Set address 0x53, write 0x32, read 6 bytes
           Set address 0x1E, write 0x03, read 6 bytes
           Set address 0x68, write 0x1B, read 8 bytes
           End

           0x04 0x53   0x07 0x01 0x32   0x06 0x06
           0x04 0x1E   0x07 0x01 0x03   0x06 0x06
           0x04 0x68   0x07 0x01 0x1B   0x06 0x08
           0x00

       M/MODES g m - Set GPIO mode

           This command sets GPIO g to mode m, typically input (read) or output (write).

           Upon success nothing is returned.  On error a negative status code will be returned.

           Each GPIO can be configured to be in one of 8 different modes. The modes are named
           Input, Output, ALT0, ALT1, ALT2, ALT3, ALT4, and ALT5.

           To set the mode use the code for the mode.

           Mode  Input Output ALT0 ALT1 ALT2 ALT3 ALT4 ALT5
           Code      R      W    0    1    2    3    4    5

           Example

           $ pigs m 4 r # Input (read)
           $ pigs m 4 w # Output (write)
           $ pigs m 4 0 # ALT 0
           $ pigs m 4 5 # ALT 5

       MG/MODEG g - Get GPIO mode

           This command returns the current mode of GPIO g.

           Upon success the value of the GPIO mode is returned.  On error a negative status code
           will be returned.

           Value      0      1    2    3    4    5    6    7
           Mode   Input Output ALT5 ALT4 ALT0 ALT1 ALT2 ALT3

           Example

           $ pigs mg 4
           1

       MICS v - Microseconds delay

           This command delays execution for v microseconds.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The main use of this command is expected to be within Scripts.

           Example

           $ pigs mics 20 # Delay 20 microseconds.
           $ pigs mics 1000000 # Delay 1 second.

           $ pigs mics 2000000
           -64
           ERROR: bad MICS delay (too large)

       MILS v - Milliseconds delay

           This command delays execution for v milliseconds.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs mils 2000 # Delay 2 seconds.

           $ pigs mils 61000
           -65
           ERROR: bad MILS delay (too large)

       NB h bits - Start notification

           This command starts notifications on handle h returned by a prior call to NO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The notification gets state changes for each GPIO specified by bits.

           Example

           $ pigs nb 0 -1 # Shorthand for GPIO 0-31.
           $ pigs nb 0 0xf0 # Get notifications for GPIO 4-7.

           $ pigs nb 1 0xf
           -25
           ERROR: unknown handle

       NC h - Close notification

           This command stops notifications on handle h returned by a prior call to NO and
           releases the handle for reuse.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs nc 0 # First call succeeds.

           $ pigs nc 1 # Second call fails.
           -25
           ERROR: unknown handle

       NO  - Request a notification

           This command requests a free notification handle.

           A notification is a method for being notified of GPIO state changes via a pipe.

           Upon success the command returns a handle greater than or equal to zero.  On error a
           negative status code will be returned.

           Notifications for handle x will be available at the pipe named /dev/pigpiox (where x
           is the handle number).

           E.g. if the command returns 15 then the notifications must be read from /dev/pigpio15.

           Example

           $ pigs no
           0

       NP h - Pause notification

           This command pauses notifications on handle h returned by a prior call to NO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Notifications for the handle are suspended until a new NB command is given for the
           handle.

           Example

           $ pigs np 0

       P/PWM u v - Set GPIO PWM value

           This command starts PWM on GPIO u with dutycycle v.  The dutycycle varies from 0 (off)
           to range (fully on).  The range defaults to 255.

           Upon success nothing is returned.  On error a negative status code will be returned.

           This and the servo functionality use the DMA and PWM or PCM peripherals to control and
           schedule the pulsewidths and dutycycles.

           The PRS command may be used to change the default range of 255.

           Example

           $ pigs p 4 64  # Start PWM on GPIO 4 with 25% dutycycle
           $ pigs p 4 128 # 50%
           $ pigs p 4 192 # 75%
           $ pigs p 4 255 # 100%

       PADG pad - Get pad drive strength

           This command gets the pad drive strength padma in mA.

           Returns the pad drive strength if OK.  On error a negative status code will be
           returned.

           Pad   GPIO
           0     0-27
           1     28-45
           2     46-53

           Example

           $ pigs padg 0
           8
           $ pigs pads 0 16
           $ pigs padg 0
           16
           pigs padg 3
           -126
           ERROR: bad pad number

       PADS pad padma - Set pad drive strength

           This command sets the pad drive strength padma in mA.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Pad   GPIO
           0     0-27
           1     28-45
           2     46-53

           Example

           $ pigs pads 0 16
           $ pigs padg 0
           16
           $ pigs pads 0 17
           -127
           ERROR: bad pad drive strength

       PARSE t - Validate script

           Validates the text t of a script without storing the script.

           Upon success nothing is returned.  On error a list of detected script errors will be
           given.

           See Scripts.

           This command may be used to find script syntax faults.

           Example

           $ pigs parse tag 100 w 22 1 mils 200 w 22 0 mils 800 jmp 100

           $ pigs parse tag 0 w 22 1 mills 50 w 22 0 dcr p10 jp 99
           Unknown command: mills
           Unknown command: 50
           Bad parameter to dcr
           Can't resolve tag 99

       PFG u - Get GPIO PWM frequency

           This command returns the PWM frequency in Hz used for GPIO u.

           Upon success the PWM frequency is returned.  On error a negative status code will be
           returned.

           For normal PWM the frequency will be that defined for the GPIO by PFS.

           If a hardware clock is active on the GPIO the reported frequency will be that set by
           HC.

           If hardware PWM is active on the GPIO the reported frequency will be that set by HP.

           Example

           $ pigs pfg 4
           800

           $ pigs pfg 34
           ERROR: GPIO not 0-31
           -2

       PFS u v - Set GPIO PWM frequency

           This command sets the PWM frequency v to be used for GPIO u.

           The numerically closest frequency to v will be selected.

           Upon success the new frequency is returned.  On error a negative status code will be
           returned.

           If PWM is currently active on the GPIO it will be switched off and then back on at the
           new frequency.

           Each GPIO can be independently set to one of 18 different PWM frequencies.

           The selectable frequencies depend upon the sample rate which may be 1, 2, 4, 5, 8, or
           10 microseconds (default 5).  The sample rate is set when the pigpio daemon is
           started.

           The frequencies for each sample rate are:

                                  Hertz

                  1: 40000 20000 10000 8000 5000 4000 2500 2000 1600
                      1250  1000   800  500  400  250  200  100   50

                  2: 20000 10000  5000 4000 2500 2000 1250 1000  800
                       625   500   400  250  200  125  100   50   25

                  4: 10000  5000  2500 2000 1250 1000  625  500  400
                       313   250   200  125  100   63   50   25   13
           sample
            rate
            (us)  5:  8000  4000  2000 1600 1000  800  500  400  320
                       250   200   160  100   80   50   40   20   10

                  8:  5000  2500  1250 1000  625  500  313  250  200
                       156   125   100   63   50   31   25   13    6

                 10:  4000  2000  1000  800  500  400  250  200  160
                       125   100    80   50   40   25   20   10    5

           Example

           pigs pfs 4 0 # 0 selects the lowest frequency.
           10

           $ pigs pfs 4 1000 # Set 1000Hz PWM.
           1000

           $ pigs pfs 4 100000 # Very big number selects the highest frequency.
           8000

       PIGPV  - Get pigpio library version

           This command returns the pigpio library version.

           Example

           $ pigs pigpv
           17

       PRG u - Get GPIO PWM range

           This command returns the dutycycle range for GPIO u.

           Upon success the range is returned.  On error a negative status code will be returned.

           If a hardware clock or hardware PWM is active on the GPIO the reported range will be
           1000000 (1M).

           Example

           $ pigs prg 4
           255

       PROC t - Store script

           This command stores a script t for later execution.

           If the script is valid a script id (>=0) is returned which is passed to the other
           script commands. On error a negative status code will be returned.

           See Scripts.

           Example

           $ pigs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
           0

           $ pigs proc tag 123 w 4 0 mils 5 w 4 1 mils 5 jmp 12
           ERROR: script has unresolved tag
           -63

       PROCD sid - Delete script

           This command deletes script sid.

           Upon success nothing is returned.  On error a negative status code will be returned.

           See Scripts.

           Example

           $ pigs procd 1

           $ pigs procd 1
           ERROR: unknown script id
           -48

       PROCP sid - Get script status and parameters

           This command returns the status of script sid as well as the current value of its 10
           parameters.

           Upon success the script status and parameters are  returned.  On error a negative
           status code will be returned.

           The script status may be one of

           0   being initialised
           1   halted
           2   running
           3   waiting
           4   failed

           See Scripts.

           Example

           $ pigs procp 0
           1 0 0 0 0 0 0 0 0 0 0

       PROCR sid pars - Run script

           This command runs stored script sid passing it up to 10 optional parameters.

           Upon success nothing is returned.  On error a negative status code will be returned.

           See Scripts.

           Example

           $ pigs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
           0

           $ pigs procr 0 50 # Run script 0 with parameter 0 of 50.

           $ pigs procp 0
           2 44 0 0 0 0 0 0 0 0 0
           $ pigs procp 0
           2 37 0 0 0 0 0 0 0 0 0
           $ pigs procp 0
           2 10 0 0 0 0 0 0 0 0 0
           $ pigs procp 0
           2 5 0 0 0 0 0 0 0 0 0
           $ pigs procp 0
           2 2 0 0 0 0 0 0 0 0 0
           $ pigs procp 0
           1 -1 0 0 0 0 0 0 0 0 0

       PROCS sid - Stop script

           This command stops a running script sid.

           Upon success nothing is returned.  On error a negative status code will be returned.

           See Scripts.

           Example

           $ pigs procs 0

           $ pigs procs 1
           -48
           ERROR: unknown script id

       PROCU sid pars - Set script parameters

           This command sets the parameters of a stored script sid passing it up to 10
           parameters.

           Upon success nothing is returned.  On error a negative status code will be returned.

           See Scripts.

           Example

           $ pigs proc tag 0 hp 18 p0 p1 mils 1000 jmp 0
           0
           $ pigs procu 0 50 500000
           $ pigs procr 0
           $ pigs procu 0 100
           $ pigs procu 0 200
           $ pigs procu 0 200 100000

       PRRG u - Get GPIO PWM real range

           This command returns the real underlying range used by GPIO u.

           If a hardware clock is active on the GPIO the reported real range will be 1000000
           (1M).

           If hardware PWM is active on the GPIO the reported real range will be approximately
           250M divided by the set PWM frequency.

           On error a negative status code will be returned.

           See PRS.

           Example

           $ pigs prrg 17
           250

           $ pigs pfs 17 0
           10
           $ pigs prrg 17
           20000

           $ pigs pfs 17 100000
           8000
           $ pigs prrg 17
           25

       PRS u v - Set GPIO PWM range

           This command sets the dutycycle range v to be used for GPIO u.  Subsequent uses of
           command P/PWM will use a dutycycle between 0 (off) and v (fully on).

           Upon success the real underlying range used by the GPIO is returned.  On error a
           negative status code will be returned.

           If PWM is currently active on the GPIO its dutycycle will be scaled to reflect the new
           range.

           The real range, the number of steps between fully off and fully on for each frequency,
           is given in the following table.

            #1   #2   #3   #4   #5   #6   #7    #8    #9
            25   50  100  125  200  250  400   500   625

           #10  #11  #12  #13  #14  #15  #16   #17   #18
           800 1000 1250 2000 2500 4000 5000 10000 20000

           The real value set by PRS is (dutycycle * real range) / range.

           See PRRG

           Example

           $ pigs prs 18 1000
           250

       PUD g p - Set GPIO pull up/down

           This command sets the internal pull/up down for GPIO g to mode p.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The mode may be pull-down (D), pull-up (U), or off (O).

           Example

           $ pigs pud 4 d # Set pull-down on GPIO 4.
           $ pigs pud 4 u # Set pull-up on GPIO 4.
           $ pigs pud 4 o # No pull-up/down on GPIO 4.

       R/READ g - Read GPIO level

           This reads the current level of GPIO g.

           Upon success the current level is returned.  On error a negative status code will be
           returned.

           Example

           $ pigs r 17 # Get level of GPIO 17.
           0

           $ pigs r 4 # Get level of GPIO 4.
           1

       S/SERVO u v - Set GPIO servo pulsewidth

           This command starts servo pulses of v microseconds on GPIO u.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The servo pulsewidth may be 0 (off), 500 (most anti-clockwise) to 2500 (most
           clockwise).

           The range supported by servos varies and should probably be determined by experiment.
           Generally values between 1000-2000 should be safe.  A value of 1500 should always be
           safe and represents the mid-point of rotation.

           You can DAMAGE a servo if you command it to move beyond its limits.

           Example

           $ pigs SERVO 17 1500

           This example causes an on pulse of 1500 microseconds duration to be transmitted on
           GPIO 17 at a rate of 50 times per second.

           This will command a servo connected to GPIO 17 to rotate to its mid-point.

           Example

           pigs s 17 0 # Switch servo pulses off.

       SERC h - Close serial handle

           This command closes a serial handle h previously opened with SERO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs serc 0 # First close okay.

           $ pigs serc 0 # Second close gives error.
           -25
           ERROR: unknown handle

       SERDA h - Check for serial data ready to read

           This command returns the number of bytes of data available to be read from the serial
           device associated with handle h.

           Upon success the count of bytes available to be read is returned (which may be 0).  On
           error a negative status code will be returned.

           Example

           $ pigs serda 0
           0

       SERO dev b sef - Open serial device dev at baud b with flags

           This command opens the serial dev at b bits per second.

           No flags are currently defined.  sef should be set to zero.

           Upon success a handle (>=0) is returned.  On error a negative status code will be
           returned.

           The device name must start with /dev/tty or /dev/serial.

           The baud rate must be one of 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400,
           4800, 9600, 19200, 38400, 57600, 115200, or 230400.

           Example

           $ pigs sero /dev/ttyAMA0 9600 0
           0

           $ pigs sero /dev/tty1 38400 0
           1

       SERR h num - Read bytes from serial handle

           This command returns up to num bytes of data read from the serial device associated
           with handle h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs serr 0 10
           5 48 49 128 144 255

           $ pigs serr 0 10
           0

       SERRB  - Read byte from serial handle

           This command returns a byte of data read from the serial device associated with handle
           h.

           Upon success a number between 0 and 255 is returned.  On error a negative status code
           will be returned.

           Example

           $ pigs serrb 0
           23
           $ pigs serrb 0
           45

       SERW h bvs - Write bytes to serial handle

           This command writes bytes bvs to the serial device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs serw 0 23 45 67 89

       SERWB h bv - Write byte to serial handle

           This command writes a single byte bv to the serial device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs serwb 0 23
           $ pigs serwb 0 0xf0

       SHELL name str - Execute a shell command

           This command uses the system call to execute a shell script name with the given string
           str as its parameter.

           The exit status of the system call is returned if OK, otherwise PI_BAD_SHELL_STATUS.

           name must exist in /opt/pigpio/cgi and must be executable.

           The returned exit status is normally 256 times that set by the shell script exit
           function.  If the script can't be found 32512 will be returned.

           The following table gives some example returned statuses.

           Script exit status   Returned system call status
           1                    256
           5                    1280
           10                   2560
           200                  51200
           script not found     32512

           Example

           # pass two parameters, hello and world
           $ pigs shell scr1 hello world
           256

           # pass three parameters, hello, string with spaces, and world
           $ pigs shell scr1 "hello 'string with spaces' world"
           256

           # pass one parameter, hello string with spaces world
           $ pigs shell scr1 "
           256

           # non-existent script
           $ pigs shell scr78 par1
           32512

       SLR u num - Read bit bang serial data from GPIO

           This command returns up to num bytes of bit bang serial data read from GPIO u.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           The GPIO u should have been initialised with the SLRO command.

           The bytes returned for each character depend upon the number of data bits db specified
           in the SLRO command.

           For db 1-8 there will be one byte per character.
           For db 9-16 there will be two bytes per character.
           For db 17-32 there will be four bytes per character.

           Example

           $ pigs slr 15 20
           6 1 0 23 45 89 0

       SLRC u - Close GPIO for bit bang serial data

           This command closes GPIO u for reading bit bang serial data.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs slrc 23

           $ pigs slrc 23
           -38
           ERROR: no serial read in progress on GPIO

       SLRI u v - Sets bit bang serial data logic levels

           This command sets the logic level for reading bit bang serial data on GPIO u.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The invert parameter v is 1 for inverted signal, 0 for normal.

           Example

           $ pigs slri 17 1 # invert logic on GPIO 17

           $ pigs slri 23 0 # use normal logic on GPIO 23

       SLRO u b db - Open GPIO for bit bang serial data

           This command opens GPIO u for reading bit bang serial data at b baud and db data bits.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The baud rate may be between 50 and 250000 bits per second.

           The received data is held in a cyclic buffer.

           It is the user's responsibility to read the data (with SLR) in a timely fashion.

           Example

           $ pigs slro 23 19200 8

           $ pigs slro 23 19200 8
           -50
           ERROR: GPIO already in use

       SPIC h - SPI close handle

           This command closes the SPI handle h returned by a prior call to SPIO.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs spic 1

           $ pigs spic 1
           -25
           ERROR: unknown handle

       SPIO c b spf - SPI open channel at baud b with flags

           This command returns a handle to a SPI device on channel c.

           Data will be transferred at b bits per second.  The flags spf may be used to modify
           the default behaviour of 4-wire operation, mode 0, active low chip select.

           Speeds between 32kbps and 125Mbps are allowed.  Speeds above 30Mbps are unlikely to
           work.

           The Pi has two SPI peripherals: main and auxiliary.

           The main SPI has two chip selects (channels), the auxiliary has three.

           The auxiliary SPI is available on all models but the A and B.

           The GPIO used are given in the following table.

                      MISO   MOSI   SCLK   CE0   CE1   CE2
           Main SPI      9     10     11     8     7     -
           Aux SPI      19     20     21    18    17    16

           The flags consists of the least significant 22 bits.

           21 20 19 18 17 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            b  b  b  b  b  b  R  T  n  n  n  n  W  A u2 u1 u0 p2 p1 p0  m  m

           mm defines the SPI mode.

           Warning:  modes 1 and 3 do not appear to work on the auxiliary SPI.

           Mode POL PHA
            0    0   0
            1    0   1
            2    1   0
            3    1   1

           px is 0 if CEx is active low (default) and 1 for active high.

           ux is 0 if the CEx GPIO is reserved for SPI (default) and 1 otherwise.

           A is 0 for the main SPI, 1 for the auxiliary SPI.

           W is 0 if the device is not 3-wire, 1 if the device is 3-wire.  Main SPI only.

           nnnn defines the number of bytes (0-15) to write before switching the MOSI line to
           MISO to read data.  This field is ignored if W is not set.  Main SPI only.

           T is 1 if the least significant bit is transmitted on MOSI first, the default (0)
           shifts the most significant bit out first.  Auxiliary SPI only.

           R is 1 if the least significant bit is received on MISO first, the default (0)
           receives the most significant bit first.  Auxiliary SPI only.

           bbbbbb defines the word size in bits (0-32).  The default (0) sets 8 bits per word.
           Auxiliary SPI only.

           The SPIR, SPIW, and SPIX commands transfer data packed into 1, 2, or 4 bytes according
           to the word size in bits.

           For bits 1-8 there will be one byte per character.
           For bits 9-16 there will be two bytes per character.
           For bits 17-32 there will be four bytes per character.

           Multi-byte transfers are made in least significant byte first order.

           E.g. to transfer 32 11-bit words 64 bytes need to be sent.

           E.g. to transfer the 14 bit value 0x1ABC send the bytes 0xBC followed by 0x1A.

           The other bits in flags should be set to zero.

           Upon success a handle (>=0) is returned.  On error a negative status code will be
           returned.

           Example

           $ pigs spio 0 100000 3 # Open channel 0 at 100kbps in mode 3.
           0

           $ pigs spio 0 32000 256 # Open channel 0 of auxiliary spi at 32kbps.
           1

       SPIR h num - SPI read bytes from handle

           This command returns num bytes read from the SPI device associated with handle h.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs spir 0 10 # Read 10 bytes from the SPI device.
           10 0 0 0 0 0 0 0 0 0 0

       SPIW h bvs - SPI write bytes to handle

           This command writes bytes bvs to the SPI device associated with handle h.

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs spiw 0 0x22 0x33 0xcc 0xff

       SPIX h bvs - SPI transfer bytes to handle

           This command writes bytes bvs to the SPI device associated with handle h.  It returns
           the same number of bytes read from the device.

           Upon success the count of returned bytes followed by the bytes themselves is returned.
           On error a negative status code will be returned.

           Example

           $ pigs spix 0 0x22 0x33 0xcc 0xff
           4 0 0 0 0

       T/TICK  - Get current tick

           This command returns the current system tick.

           Tick is the number of microseconds since system boot.

           As tick is an unsigned 32 bit quantity it wraps around after 2^32 microseconds, which
           is approximately 1 hour 12 minutes.

           Example

           $ pigs t mils 1000 t
           3691823946
           3692833987

       TRIG u pl L - Send a trigger pulse

           This command sends a trigger pulse of pl microseconds at level L to GPIO u.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The GPIO is set to not level at the end of the pulse.

           Example

           $ pigs trig 4 10 1

           $ pigs trig 4 51 1
           -46
           ERROR: trigger pulse > 50 microseconds

       W/WRITE g L - Write GPIO level

           This command sets GPIO g to level L.  The level may be 0 (low, off, clear) or 1 (high,
           on, set).

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs w 23 0
           $ pigs w 23 1

           $ pigs w 23 2
           -5
           ERROR: level not 0-1

       WDOG u v - Set GPIO watchdog

           This command sets a watchdog of v milliseconds on GPIO u.

           Upon success nothing is returned.  On error a negative status code will be returned.

           The watchdog is nominally in milliseconds.

           One watchdog may be registered per GPIO.

           The watchdog may be cancelled by setting timeout to 0.

           Once a watchdog has been started monitors of the GPIO will be triggered every timeout
           interval after the last GPIO activity.  The watchdog expiry will be indicated by a
           special TIMEOUT value.

           Example

           $ pigs wdog 23 90000
           -15
           ERROR: timeout not 0-60000

           $ pigs wdog 23 9000

           This example causes a report to be written to any notification pipes listening on GPIO
           23 whenever GPIO 23 changes state or approximately every 9000 ms.

       WVAG trips - Add generic pulses to waveform

           This command adds 1 one or more triplets trips of GPIO on, GPIO off, delay to the
           existing waveform (if any).

           Upon success the total number of pulses in the waveform so far is returned.  On error
           a negative status code will be returned.

           The triplets will be added at the start of the existing waveform.  If they are to
           start offset from the start then the first triplet should consist solely of a delay
           i.e. 0 0 offset.

           Example

           $ pigs wvag 0x10 0x80 1000 0x80 0x10 9000
           2

           $ pigs wvag 0 0 10000 0x10 0x80 1000 0x80 0x10 9000
           4

       WVAS u b db sb o bvs - Add serial data to waveform

           This command adds a waveform representing serial data bvs to GPIO u at b baud to the
           existing waveform (if any).  The serial data starts o microseconds from the start of
           the waveform.

           Upon success the total number of pulses in the waveform so far is returned.  On error
           a negative status code will be returned.

           The serial data is formatted as one start bit, db data bits, and sb/2 stop bits.

           The baud rate may be between 50 and 1000000 bits per second.

           It is legal to add serial data streams with different baud rates to the same waveform.

           The bytes required for each character depend upon db.

           For db 1-8 there will be one byte per character.
           For db 9-16 there will be two bytes per character.
           For db 17-32 there will be four bytes per character.

           Example

           $ pigs wvas 4 9600 8 2 0 0x30 0x31 0x32 0x33
           23

           $ pigs wvas 7 38400 8 2 0 0x41 0x42
           35

       WVTAT  - Returns the current transmitting waveform

           This command returns the id of the waveform currently being transmitted.  Chained
           waves are not supported.

           Returns the waveform id or one of the following special values:

           9998 - transmitted wave not found
           9999 - no wave being transmitted

           Example

           $ pigs wvtat
           9999

       WVBSY  - Check if waveform is being transmitted

           This command checks to see if a waveform is currently being transmitted.

           Returns 1 if a waveform is currently being transmitted, otherwise 0.

           Example

           $ pigs wvbsy
           0

       WVCHA bvs - Transmits a chain of waveforms

           This command transmits a chain of waveforms.

           NOTE: Any hardware PWM started by HP will be cancelled.

           The waves to be transmitted are specified by the contents of bvs which contains an
           ordered list of wave_ids and optional command codes and related data.

           Upon success 0 is returned.  On error a negative status code will be returned.

           Each wave is transmitted in the order specified.  A wave may occur multiple times per
           chain.

           A blocks of waves may be transmitted multiple times by using the loop commands. The
           block is bracketed by loop start and end commands.  Loops may be nested.

           Delays between waves may be added with the delay command.

           The following command codes are supported:

           Name           Cmd & Data   Meaning
           Loop Start     255 0        Identify start of a wave block
           Loop Repeat    255 1 x y    loop x + y*256 times
           Delay          255 2 x y    delay x + y*256 microseconds
           Loop Forever   255 3        loop forever

           If present Loop Forever must be the last entry in the chain.

           The code is currently dimensioned to support a chain with roughly 600 entries and 20
           loop counters.

           Example

           #!/bin/bash

           GPIO=4
           WAVES=5

           pigs m $GPIO w

           for ((i=0; i<$WAVES; i++))
           do
              pigs wvag $((1<<GPIO)) 0 20 0 $((1<<GPIO)) $(((i+1)*200))
              w[i]=$(pigs wvcre)
           done

           # transmit waves 4+3+2
           # loop start
           #    transmit waves 0+0+0
           #    loop start
           #       transmit waves 0+1
           #       delay 5000us
           #    loop end (repeat 30 times)
           #    loop start
           #       transmit waves 2+3+0
           #       transmit waves 3+1+2
           #    loop end (repeat 10 times)
           # loop end (repeat 5 times)
           # transmit waves 4+4+4
           # delay 20000us
           # transmit waves 0+0+0

           pigs wvcha .br
              ${w[4]} ${w[3]} ${w[2]} .br
              255 0 .br
                 ${w[0]} ${w[0]} ${w[0]} .br
                 255 0 .br
                    ${w[0]} ${w[1]} .br
                    255 2 0x88 0x13 .br
                 255 1 30 0 .br
                 255 0 .br
                    ${w[2]} ${w[3]} ${w[0]} .br
                    ${w[3]} ${w[1]} ${w[2]} .br
                 255 1 10 0 .br
              255 1 5 0 .br
              ${w[4]} ${w[4]} ${w[4]} .br
              255 2 0x20 0x4E .br
              ${w[0]} ${w[0]} ${w[0]}

           while [[ $(pigs wvbsy) -eq 1 ]]; do sleep 0.1; done

           for ((i=0; i<$WAVES; i++)); do echo ${w[i]}; pigs wvdel ${w[i]}; done

       WVCLR  - Clear all waveforms

           This command clears all waveforms.

           Nothing is returned.

           Example

           $ pigs wvclr

       WVCRE  - Create a waveform

           This command creates a waveform from the data provided by the prior calls to the WVAG
           and WVAS commands.

           Upon success a wave id (>=0) is returned.  On error a negative status code will be
           returned.

           The data provided by the WVAG and WVAS commands is consumed by this command.

           As many waveforms may be created as there is space available.  The wave id is passed
           to WVTX or WVTXR to specify the waveform to transmit.

           Normal usage would be

           Step 1. WVCLR to clear all waveforms and added data.

           Step 2. WVAG/WVAS calls to supply the waveform data.

           Step 3. WVCRE to create the waveform and get a unique id.

           Repeat steps 2 and 3 as needed.

           Step 4. WVTX or WVTXR with the id of the waveform to transmit.

           A waveform comprises of one or more pulses.

           A pulse specifies

           1) the GPIO to be switched on at the start of the pulse.
           2) the GPIO to be switched off at the start of the pulse.
           3) the delay in microseconds before the next pulse.

           Any or all the fields can be zero.  It doesn't make any sense to set all the fields to
           zero (the pulse will be ignored).

           When a waveform is started each pulse is executed in order with the specified delay
           between the pulse and the next.

           Example

           $ pigs wvas 4 9600 0 23 45 67 89 90
           37
           $ pigs wvcre
           0

           $ pigs wvcre
           -69
           ERROR: attempt to create an empty waveform

       WVCAP percent - Create a waveform of fixed size

           Create a waveform of fixed size. Similar to WVCRE, this command creates a waveform but
           pads the consumed resources to a fixed size, specified as a percent of the total
           resources. Padded waves of equal size can be re-cycled efficiently allowing newly
           created waves to re-use the resources of deleted waves of the same dimension.

           Upon success a wave id (>=0) is returned. On error a negative status code will be
           returned.

           The data provided by the WVAG and WVAS commands are consumed by this command.

           As many waveforms may be created as there is space available. The wave id is passed to
           WVTX or WVTXR to specify the waveform to transmit.

           Normal usage would be

           Step 1. WVCLR to clear all waveforms and added data.

           Step 2. WVAG/WVAS calls to supply the waveform data.

           Step 3. WVCAP to create a waveform of a uniform size.

           Step 4. WVTX or WVTXR with the id of the waveform to transmit.

           Repeat steps 2 - 4 as needed.

           Step 5. Any wave id can now be deleted and another wave of the same size can be
           created in its place.

           Example

           Example

           # Create a wave that consumes 50% of the total resource:

           $ pigs wvag 16 0 5000000 0 16 5000000
           2
           $ pigs wvcap 50
           0
           $ pigs wvtx 0
           11918

       WVDEL wid - Delete selected waveform

           This command deletes the waveform with id wid.

           The wave is flagged for deletion.  The resources used by the wave will only be reused
           when either of the following apply.

           - all waves with higher numbered wave ids have been deleted or have been flagged for
           deletion.

           - a new wave is created which uses exactly the same resources as the current wave (see
           the C source for gpioWaveCreate for details).

           Upon success nothing is returned.  On error a negative status code will be returned.

           Example

           $ pigs wvdel 0

           $ pigs wvdel 0
           -66
           ERROR: non existent wave id

       WVHLT  - Stop waveform

           This command aborts the transmission of the current waveform.

           Nothing is returned.

           This command is intended to stop a waveform started in the repeat mode.

           Example

           $ pigs wvhlt

       WVNEW  - Initialise a new waveform

           This clears any existing waveform data ready for the creation of a new waveform.

           Nothing is returned.

           Example

           $ pigs wvnew

       WVSC ws - Get waveform DMA CB stats

           The statistic requested by ws is returned.

           ws identifies the subcommand as follows.

           0 Get Cbs
           1 Get High Cbs
           2 Get Max Cbs

           Example

           $ pigs wvas 4 9600 0 23 45 67 89 90
           37

           $ pigs wvsc 0
           74
           $ pigs wvsc 1
           74
           $ pigs wvsc 2
           25016

       WVSM ws - Get waveform time stats

           The statistic requested by ws is returned.

           ws identifies the subcommand as follows.

           0 Get Micros
           1 Get High Micros
           2 Get Max Micros

           Example

           $ pigs wvsm 0
           5314
           $ pigs wvsm 1
           5314
           $ pigs wvsm 2
           1800000000

       WVSP ws - Get waveform pulse stats

           The statistic requested by ws is returned.

           ws identifies the subcommand as follows.

           0 Get Pulses
           1 Get High Pulses
           2 Get Max Pulses

           Example

           $ pigs wvsp 0
           37
           $ pigs wvsp 1
           37
           $ pigs wvsp 2
           12000

       WVTX wid - Transmits waveform once

           This command transmits the waveform with id wid once.

           NOTE: Any hardware PWM started by HP will be cancelled.

           Upon success the number of DMA control blocks in the waveform is returned.  On error a
           negative status code will be returned.

           Example

           $ pigs wvtx 1
           75

           $ pigs wvtx 2
           -66
           ERROR: non existent wave id

       WVTXM wid wmde - Transmits waveform using mode

           This command transmits the waveform with id wid using mode wmde.

           The mode may be send once (0), send repeatedly (1), send once but first sync with
           previous wave (2), or send repeatedly but first sync with previous wave (3).

           WARNING: bad things may happen if you delete the previous waveform before it has been
           synced to the new waveform.

           NOTE: Any hardware PWM started by HP will be cancelled.

           Upon success the number of DMA control blocks in the waveform is returned.  On error a
           negative status code will be returned.

           Example

           $ pigs wvtxm 1 3
           75

           $ pigs wvtxm 2 0
           -66
           ERROR: non existent wave id

       WVTXR wid - Transmits waveform repeatedly

           This command transmits the waveform with id wid repeatedly.

           NOTE: Any hardware PWM started by HP will be cancelled.

           Upon success the number of DMA control blocks in the waveform is returned.  On error a
           negative status code will be returned.

           Example

           $ pigs wvtxr 1
           75

           $ pigs wvtxr 2
           -66
           ERROR: non existent wave id

PARAMETERS

       actv - 0-1000000

       The number of microseconds level changes are reported for once a noise filter has been
       triggered (by stdy microseconds of a stable level).

       b - baud
       The command expects the baud rate in bits per second for the transmission of serial data
       (I2C/SPI/serial link, waves).

       bctl - BSC control word
       The command expects a BSC control word, see BSCX.

       bit - bit value (0-1)
       The command expects 0 or 1.

       bits - a bit mask
       A mask is used to select one or more GPIO.  A GPIO is selected if bit (1<<GPIO) is set in
       the mask.

       E.g. a mask of 6 (binary 110) select GPIO 1 and 2, a mask of 0x103 (binary 100000011)
       selects GPIO 0, 1, and 8.

       bv - a byte value (0-255)
       The command expects a byte value.

       bvs - byte values (0-255)
       The command expects one or more byte values.

       c - SPI channel (0-1)
       The command expects a SPI channel.

       cf - hardware clock frequency (4689-250M, 13184-375M for the BCM2711)
       The command expects a frequency.

       cs - GPIO (0-31)
       The GPIO used for the slave select signal when bit banging SPI.

       db - serial data bits (1-32)
       The command expects the number of data bits per serial character.

       dev - a tty serial device (/dev/tty* or /dev/serial*)
       The command expects the name of a tty serial device, e.g.

       /dev/ttyAMA0
       /dev/ttyUSB0
       /dev/tty0
       /dev/serial0

       event - 0-31
       An event is a signal used to inform one or more consumers to start an action.

       file - a file name
       The file name must match an entry in /opt/pigpio/access.

       from - 0-2
       Position to seek from FS.

           From
       0   start
       1   current position
       2   end

       g - GPIO (0-53)
       The command expects a GPIO.

       There are 54 General Purpose Input Outputs (GPIO) named gpio0 through gpio53.

       They are split into two banks.  Bank 1 consists of gpio0 through gpio31.  Bank 2 consists
       of gpio32 through gpio53.

       All the GPIO which are safe for the user to read and write are in bank 1.  Not all GPIO in
       bank 1 are safe though. Type 1 boards have 17 safe GPIO.  Type 2 boards have 21. Type 3
       boards have 26.

       See HWVER.

       The user GPIO are marked with an X in the following table.

                 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15
       Type 1    X  X  -  -  X  -  -  X  X  X  X  X  -  -  X  X
       Type 2    -  -  X  X  X  -  -  X  X  X  X  X  -  -  X  X
       Type 3          X  X  X  X  X  X  X  X  X  X  X  X  X  X

                16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
       Type 1    -  X  X  -  -  X  X  X  X  X  -  -  -  -  -  -
       Type 2    -  X  X  -  -  -  X  X  X  X  -  X  X  X  X  X
       Type 3    X  X  X  X  X  X  X  X  X  X  X  X  -  -  -  -

       You are not prevented from writing to unsafe GPIO.  The consequences of doing so range
       from no effect, to a crash, or corrupted data.

       h - handle (>=0)
       The command expects a handle.

       A handle is a number referencing an object opened by one of FO, I2CO, NO, SERO, SPIO.

       ib - I2C bus (>=0)
       The command expects an I2C bus number.

       id - I2C device (0-0x7F)
       The command expects the address of an I2C device.

       if - I2C flags (0)
       The command expects an I2C flags value.  No flags are currently defined.

       L - level (0-1)
       The command expects a GPIO level.

       m - mode (RW540123)
       The command expects a mode character.

       Each GPIO can be configured to be in one of 8 different modes. The modes are named Input,
       Output, ALT0, ALT1, ALT2, ALT3, ALT4, and ALT5.

       To set the mode use the code for the mode.

       The value is returned by the mode get command.

       Mode    Input   Output   ALT0   ALT1   ALT2   ALT3   ALT4   ALT5
       Code      R        W       0      1      2      3      4      5
       Value     0        1       4      5      6      7      3      2

       miso - GPIO (0-31)
       The GPIO used for the MISO signal when bit banging SPI.

       mode - file open mode
       One of the following values.

               Value   Meaning
       READ      1     open file for reading
       WRITE     2     open file for writing
       RW        3     open file for reading and writing

       The following values can be or'd into the mode.

                Value   Meaning
       APPEND   4       All writes append data to the end of the file
       CREATE   8       The file is created if it doesn't exist
       TRUNC    16      The file is truncated

       mosi - GPIO (0-31)
       The GPIO used for the MOSI signal when bit banging SPI.

       name - the name of a script
       Only alphanumeric characters, '-' and '_' are allowed in the name.

       num - maximum number of bytes to return (1-)
       The command expects the maximum number of bytes to return.

       For the I2C and SPI commands the requested number of bytes will always be returned.

       For the serial and file commands the smaller of the number of bytes available to be read
       (which may be zero) and num bytes will be returned.

       o - offset (>=0)
       Serial data is stored offset microseconds from the start of the waveform.

       p - PUD (ODU)
       The command expects a PUD character.

       Each GPIO can be configured to use or not use an internal pull up or pull down resistor.
       This is useful to provide a default state for inputs.

       A pull up will default the input to 1 (high).

       A pull down will default the input to 0 (low).

       To set the pull up down state use the command character for the state.

       Pull Up Down      Off Pull Down Pull Up
       Command Character   O         D       U

       There is no mechanism to read the pull up down state.

       pad - 0-2
       A set of GPIO which share common drivers.

       Pad   GPIO
       0     0-27
       1     28-45
       2     46-53

       padma - 1-16
       The mA which may be drawn from each GPIO whilst still guaranteeing the high and low
       levels.

       pars - script parameters
       The command expects 0 to 10 numbers as parameters to be passed to the script.

       pat - a file name pattern
       A file path which may contain wildcards.  To be accessible the path must match an entry in
       /opt/pigpio/access.

       pdc - hardware PWM dutycycle (0-1000000)
       The command expects a dutycycle.

       percent - percent (1-100)
       The percent of wave resources to allocate to a wave.  It can be useful to create waves of
       fixed sizes to prevent wave fragmentation (where there are plenty of resources but not a
       large enough contiguous space).

       pf - hardware PWM frequency (1-125M, 1-187.5M for the BCM2711)
       The command expects a frequency.

       pl - pulse length (1-100)
       The command expects a pulse length in microseconds.

       r - register (0-255)
       The command expects an I2C register number.

       sb - serial stop (half) bits (2-8)
       The command expects the number of stop (half) bits per serial character.

       scl - user GPIO (0-31)
       The command expects the number of the GPIO to be used for SCL when bit banging I2C.

       sclk - user GPIO (0-31)
       The GPIO used for the SCLK signal when bit banging SPI.

       sda - user GPIO (0-31)
       The command expects the number of the GPIO to be used for SDA when bit banging I2C.

       sef - serial flags (32 bits)
       The command expects a flag value.  No serial flags are currently defined.

       sid - script id (>= 0)
       The command expects a script id as returned by a call to PROC.

       spf - SPI flags (32 bits)
       See SPIO and BSPIO.

       stdy - 0-300000

       The number of microseconds level changes must be stable for before reporting the level
       changed (FG) or triggering the active part of a noise filter (FN).

       str - a string
       The command expects a string.

       t - a string
       The command expects a string.

       trips - triplets
       The command expects 1 or more triplets of GPIO on, GPIO off, delay.

       E.g. 0x400000 0 100000 0 0x400000 900000 defines two pulses as follows

            GPIO on           GPIO off           delay
       0x400000 (GPIO 22)           0 (None) 100000 (1/10th s)
                 0 (None) 0x400000 (GPIO 22) 900000 (9/10th s)

       u - user GPIO (0-31)
       The command expects the number of a user GPIO.

       A number of commands are restricted to GPIO in bank 1, in particular the PWM commands, the
       servo command, the watchdog command, and the notification command.

       It is your responsibility to ensure that the PWM and servo commands are only used on safe
       GPIO.

       See g

       uvs - values
       The command expects an arbitrary number of >=0 values (possibly none).  Any after the
       first two must be <= 255.

       v - value
       The command expects a number.

       wid - wave id (>=0)
       The command expects a wave id.

       When a waveform is created it is given an id (0, 1, 2, ...).

       wmde - mode (0-3)
       The command expects a wave transmission mode.

       0 = send once
       1 = send repeatedly
       2 = send once but first sync with previous wave
       3 = send repeatedly but first sync with previous wave

       ws - wave stats sucommand (0-2)
       The command expects a subcommand.

       0 = current value.
       1 = highest value so far.
       2 = maximum possible value.

       wv - word value (0-65535)
       The command expects a word value.

SCRIPTS

       Scripts are programs to be stored and executed by the pigpio daemon.  They are intended to
       mitigate any performance problems associated with the pigpio daemon server/client model.

   Example
       A trivial example might be useful.  Suppose you want to toggle a GPIO on and off as fast
       as possible.

       From the command line you could write

       for ((i=0; i<1000;i++)); do pigs w 22 1 w 22 0; done

       Timing that you will see it takes about 14 seconds, or roughly 70 toggles per second.

       Using the pigpio Python module you could use code such as

       #!/usr/bin/env python

       import time

       import pigpio

       PIN=4

       TOGGLE=10000

       pi = pigpio.pi() # Connect to local Pi.

       s = time.time()

       for i in range(TOGGLE):
          pi.write(PIN, 1)
          pi.write(PIN, 0)

       e = time.time()

       print("pigpio did {} toggles per second".format(int(TOGGLE/(e-s))))

       pi.stop()

       Timing that shows a speed improvement to roughly 800 toggles per second.

       Now let's use a script.

       pigs proc tag 999 w 22 1 w 22 0 dcr p0 jp 999

       Ignore the details for now.

       Let's time the script running.

       Again, ignore the details for now.

       time (pigs procr 0 10000000; while a=$(pigs procp 0); [[ ${a::1} -eq 2 ]];.br
        do sleep 0.2; done)

       The script takes roughly 12 seconds to complete, or 800,000 toggles per second.

       That is the advantage of a stored script.

       Some details.

       pigs proc tag 999 w 22 1 w 22 0 dcr p0 jp 999

       proc introduces a script.  Everything after proc is part of the script.
       tag 999 names the current position in the script.
       w 22 1 writes 1 to GPIO 22.
       w 22 0 writes 0 to GPIO 22.
       dcr p0 decrements parameter 0.
       jp 999 jumps to tag 999 if the result is positive.

       time (pigs procr 0 10000000; while a=$(pigs procp 0); [[ ${a::1} -eq 2 ]];.br
        do sleep 0.2; done)

       pigs procr 0 10000000 starts script 0 with parameter 0 of 10 million.

       The rest is bash apart from

       pigs procp 0 asks for the status and parameters of script 0.  The status will be 2 while
       the script is running and 1 when it is complete.

   Virtual machine
       A script runs within a virtual machine with

       a 32 bit accumulator A.
       a flags register F.
       a program counter PC.

       Each script has

       10 parameters named 0 through 9.
       150 variables named 0 through 149.
       50 labels which are named by any unique number.

   Commands
       Many pigpio commands may be used within a script.  However some commands do not work
       within the script model as designed and are not permitted.

       The following commands are not permitted within a script:

       File - FL FO FR FW

       I2C - BI2CZ I2CPK I2CRD I2CRI I2CRK I2CWD I2CWI I2CWK I2CZ

       Misc - BSCX CF1 CF2 SHELL

       Script control - PARSE PROC PROCD PROCP PROCR PROCS PROCU

       Serial - SERO SERR SERW SLR

       SPI - BSPIO BSPIX SPIR SPIW SPIX

       Waves - WVAG WVAS WVCHA WVGO WVGOR

       The following commands are only permitted within a script:

       Command Description                                   Definition
       ADD x   Add x to accumulator                          A+=x; F=A
       AND x   And x with accumulator                        A&=x; F=A
       CALL L  Call subroutine at tag L                      push(PC+1); PC=L
       CMP x   Compare x with accumulator                    F=A-x
       DCR y   Decrement register                            --*y; F=*y
       DCRA    Decrement accumulator                         --A; F=A
       DIV x   Divide x into accumulator                     A/=x; F=A
       EVTWT   Wait for an event to occur                    A=wait(x); F=A
       HALT    Halt                                          Halt
       INR y   Increment register                            ++*y; F=*y
       INRA    Increment accumulator                         ++A; F=A
       JM L    Jump if minus to tag L                        if (F<0) PC=L
       JMP L   Jump to tag L                                 PC=L
       JNZ L   Jump if non-zero to tag L                     if (F) PC=L
       JP L    Jump if positive to tag L                     if (F>=0) PC=L
       JZ L    Jump if zero to tag L                         if (!F) PC=L
       LD y x  Load register with x                          *y=x
       LDA x   Load accumulator with x                       A=x
       MLT x   Multiply x with accumulator                   A*=x; F=A
       MOD x   Modulus x with accumulator                    A%=x; F=A
       OR x    Or x with accumulator                         A|=x; F=A
       POP y   Pop register                                  y=pop()
       POPA    Pop accumulator                               A=pop()
       PUSH y  Push register                                 push(y)
       PUSHA   Push accumulator                              push(A)
       RET     Return from subroutine                        PC=pop()
       RL y x  Rotate left register x bits                   *y<<=x; F=*y
       RLA x   Rotate left accumulator x bits                A<<=x; F=A
       RR y x  Rotate right register x bits                  *y>>=x; F=*y
       RRA x   Rotate right accumulator x bits               A>>=x; F=A
       STA y   Store accumulator in register                 y=A
       SUB x   Subtract x from accumulator                   A-=x; F=A
       SYS str Run external script (/opt/pigpio/cgi/str)     system(str); F=A
       TAG L   Label the current script position             N/A
       WAIT x  Wait for a GPIO in x to change state          A=wait(x); F=A
       X y1 y2 Exchange contents of registers y1 and y2      t=*y1;*y1=*y2;*y2=t
       XA y    Exchange contents of accumulator and register t=A;A=*y;*y=t
       XOR x   Xor x with accumulator                        A^=x; F=A

       x may be a constant, a parameter (p0-p9), or a variable (v0-v149).

       y may be a parameter (p0-p9), or a variable (v0-v149).  If p or v isn't specified y is
       assumed to be a variable.

       The EVTWT command parameter is a bit-mask with 1 set for events of interest.

       The WAIT command parameter is a bit-mask with 1 set for GPIO of interest.

       The SYS script receives two unsigned parameters: the accumulator A and the current GPIO
       levels.

SEE ALSO

       pigpiod(1), pig2vcd(1), pigpio(3), pigpiod_if(3), pigpiod_if2(3)

AUTHOR

       joan@abyz.me.uk