Provided by: owfs-doc_2.8p13+dfsg1-5build1_all bug

NAME

       DS2770 - Battery Monitor and Charge Controller

SYNOPSIS

   Temperature Voltage Current Memory and Switch.
       2E  [.]XXXXXXXXXXXX[XX][/[  amphours  |  current | currentbias | lock.[0-2|ALL] | memory |
       pages/page.[0-2|ALL] | PIO | sensed | temperature | vbias | vis | volt | volthours |
       charge | cini | cstat0 | cstat1 | ctype | defaultpmod | pmod | refresh | timer |
       address | crc8 | id | locator | r_address | r_id | r_locator | type ]]

   Thermocouple
       2E   [.]XXXXXXXXXXXX[XX][/[   temperature   |   typeX/range_low   |   typeX/range_high   |
       typeX/temperature

FAMILY CODE

       2E

SPECIAL PROPERTIES

   amphours
       read-write, floating point
       Accumulated  amperage read by current sensor. Units are in Amp-hr (Assumes internal 25mOhm
       resistor). Derived from volthours / Rinternal.
       Formally amphours is the integral of current - currentbias over time.

   current
       read-only, floating point
       Current reading. Units are in Amp (Assumes internal 25 mOhm resistor). Derived from vis  /
       Rinternal.

   currentbias
       read-write, floating point
       Fixed  offset  applied  to  each  current measurement. Used in the amphours value. Assumes
       internal 25mOhm resistor. Units are Amp and range from -.08A to .08A.
       Derived from vbias / Rinternal.

   lock.[0-2|ALL]
       read-write, yes-no
       Lock either of the three eprom pages to prevent further writes. Apparently setting lock is
       permanent.

   memory
       read-write, binary
       Access  to  the full 256 byte memory range. Much of this space is reserved or special use.
       User space is the page area.
       See the DATASHEET for a full memory map.

   pages/pages.[0-2|ALL]
       read-write, binary Two 16 byte  and one 8 byte areas of memory for user  application.  The
       lock property can prevent further alteration.
       NOTE  that  the page property is different from the common OWFS implementation in that all
       of memory is not accessible.

   PIO
       write-only, yes-no
       Controls the PIO pin allowing external switching.
       Writing "1" turns the PIO pin on (conducting). Writing "0" makes the  pin  non-conducting.
       The  logical  state of the voltage can be read with the sensed property. This will reflect
       the current voltage at the pin, not the value sent to PIO
       Note also that PIO will also be  altered  by  the  power-status  of  the  DS2670  See  the
       datasheet for details.

   sensed
       read-only, yes-no
       The  logical  voltage  at the PIO pin. Useful only if the PIO property is set to "0" (non-
       conducting).
       Value will be 0 or 1 depending on the voltage threshold.

   temperature
       read-only, floating point
       Temperature read by the chip at high resolution (~13 bits). Units are  selected  from  the
       invoking command line. See owfs(1) or owhttpd(1) for choices. Default is Celsius.
       Conversion is continuous.

   vbias
       read-write, floating point
       Fixed  offset  applied to each vis measurement. Used for the volthours value. Units are in
       Volts.
       Range -2.0mV to 2.0mV

   vis
       read-only, floating point
       Current sensor reading (unknown external resistor). Measures the voltage gradient  between
       the Vis pins. Units are in Volts
       The vis readings are integrated over time to provide the volthours property.
       The  current  reading  is  derived  from  vis  assuming  the  internal 25 mOhm resistor is
       employed. There is no way to know this through software.

   volt
       read-only, floating point
       Voltage read at the voltage sensor;. This is separate from the vis voltage  that  is  used
       for current measurement. Units are Volts
       Range is between 0 and 4.75V

   volthours
       read-write, floating point
       Integral of vis - vbias over time. Units are in volthours

THERMOCOUPLE

   typeX/
       directory
       Thermocouple  circuit  using  the DS2770 (3) to read the Seebeck voltage and the reference
       temperature. Since the type interpretation of the values  read  depends  on  the  type  of
       thermocouple,  the  correct directory must be chosen. Supported thermocouple types include
       types B, E, J, K, N, R, S and T.

   typeX/range_low typeX/ranges_high
       read-only, flaoting point
       The lower and upper temperature supported by this thermocouple (at least by the conversion
       routines). In the globally chosen temperature units.

   typeX/temperature
       read-only, floating point
       Thermocouple  temperature.  Requires  a  voltage  and  temperature conversion. Returned in
       globally chosen temperature units.
       Note: there are two types of temperature measurements possible. The temperature  value  in
       the   main   device  directory  is  the  reference  temperature  read  at  the  chip.  The
       typeX/temperature value is at the thermocouple junction, probably remote from the chip.

OBSCURE PROPERTIES

   charge
       write-only, yes-no
       Trigger the start (1) or stop(0) of charging. see the DATASHEET for details.

   cini cstat0 cstat1 ctype pmod
       varies, yes-no
       Bit flags corresponding to various battery management  functions  of  the  chip.  See  the
       DATASHEET for details of the identically named entries.
       In  general, writing "0" corresponds to a 0 bit value, and non-zero corresponds to a 1 bit
       value.

   defaultpmod
       read-write, yes-no
       Default power-on state for the corresponding properties.

   refresh
       write-only, yes-no
       Writing anything to this file causes a refresh of parameters. See the

   timer
       read-write, floating point
       A charge timer in units of hours.  See the DATASHEET for details.

STANDARD PROPERTIES

   address
   r_address
       read-only, ascii
       The entire 64-bit unique ID. Given as upper case hexidecimal digits (0-9A-F).
       address starts with the family code
       r address is the address in reverse order, which is often used in other  applications  and
       labeling.

   crc8
       read-only, ascii
       The  8-bit  error  correction  portion.  Uses  cyclic  redundancy check. Computed from the
       preceding 56 bits of the unique ID number. Given as upper case hexidecimal  digits  (0-9A-
       F).

   family
       read-only, ascii
       The  8-bit  family  code.  Unique  to each type of device. Given as upper case hexidecimal
       digits (0-9A-F).

   id
   r_id
       read-only, ascii
       The 48-bit middle portion of the unique ID number. Does not include  the  family  code  or
       CRC. Given as upper case hexidecimal digits (0-9A-F).
       r id is the id in reverse order, which is often used in other applications and labeling.

   locator
   r_locator
       read-only, ascii
       Uses  an  extension  of  the 1-wire design from iButtonLink company that associated 1-wire
       physical connections with a unique 1-wire code. If the connection is behind a Link Locator
       the  locator  will  show  a  unique 8-byte number (16 character hexidecimal) starting with
       family code FE.
       If no Link Locator is between the device and the master, the locator field will be all FF.
       r locator is the locator in reverse order.

   present (DEPRECATED)
       read-only, yes-no
       Is the device currently present on the 1-wire bus?

   type
       read-only, ascii
       Part name assigned by Dallas Semi. E.g.  DS2401 Alternative packaging  (iButton  vs  chip)
       will not be distiguished.

ALARMS

       None.

DESCRIPTION

   1-Wire
       1-wire  is  a  wiring  protocol  and series of devices designed and manufactured by Dallas
       Semiconductor, Inc. The bus is a low-power low-speed low-connector scheme where  the  data
       line can also provide power.

       Each  device  is  uniquely  and  unalterably numbered during manufacture. There are a wide
       variety of devices, including memory, sensors (humidity,  temperature,  voltage,  contact,
       current),  switches,  timers  and  data  loggers.  More complex devices (like thermocouple
       sensors) can be built with these basic devices. There are also 1-wire  devices  that  have
       encryption included.

       The  1-wire  scheme uses a single bus master and multiple slaves on the same wire. The bus
       master initiates  all  communication.  The  slaves  can  be  individually  discovered  and
       addressed using their unique ID.

       Bus  masters  come in a variety of configurations including serial, parallel, i2c, network
       or USB adapters.

   OWFS design
       OWFS is a suite of programs that designed to make the 1-wire bus and  its  devices  easily
       accessible.  The underlying priciple is to create a virtual filesystem, with the unique ID
       being the directory, and the individual properties of the device are represented as simple
       files that can be read and written.

       Details of the individual slave or master design are hidden behind a consistent interface.
       The goal is to provide an easy set of tools for a software designer to  create  monitoring
       or  control  applications.  There are some performance enhancements in the implementation,
       including data caching,  parallel  access  to  bus  masters,  and  aggregation  of  device
       communication.  Still  the  fundemental  goal  has  been  ease  of  use,  flexibility  and
       correctness rather than speed.

   DS2770
       The DS2770 (3) is a battery  charging  controller.  It  has  elaborate  charge  estimation
       algorithms built in.

       A  number  of  interesting  devices  can be built with the DS2770 including thermocouples.
       Support for thermocouples in built into the software, using the embedded thermister as the
       cold junction temperature.

ADDRESSING

       All  1-wire  devices  are factory assigned a unique 64-bit address. This address is of the
       form:

       Family Code
              8 bits

       Address
              48 bits

       CRC    8 bits

       Addressing under OWFS is in hexidecimal, of form:

              01.123456789ABC

       where 01 is an example 8-bit family code, and 12345678ABC is an example 48 bit address.

       The dot is optional, and the CRC code can included. If included, it must be correct.

DATASHEET

       http://pdfserv.maxim-ic.com/en/ds/DS2770.pdf

SEE ALSO

   Programs
       owfs (1) owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1)  owwrite  (1)  owpresent
       (1) owtap (1)

   Configuration and testing
       owfs (5) owtap (1) owmon (1)

   Language bindings
       owtcl (3) owperl (3) owcapi (3)

   Clocks
       DS1427 (3) DS1904(3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3) DS2417 (3)

   ID
       DS2401 (3) DS2411 (3) DS1990A (3)

   Memory
       DS1982  (3)  DS1985  (3) DS1986 (3) DS1991 (3) DS1992 (3) DS1993 (3) DS1995 (3) DS1996 (3)
       DS2430A (3) DS2431 (3) DS2433 (3) DS2502 (3) DS2506 (3) DS28E04 (3) DS28EC20 (3)

   Switches
       DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3)

   Temperature
       DS1822 (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3) DS1921 (3) DS1821  (3)
       DS28EA00  (3)  DS28E04  (3)  EDS0064  (3)  EDS0065 (3) EDS0066 (3) EDS0067 (3) EDS0068 (3)
       EDS0071 (3) EDS0072 (3)

   Humidity
       DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)

   Voltage
       DS2450 (3)

   Resistance
       DS2890 (3)

   Multifunction (current, voltage, temperature)
       DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3) DS2760  (3)  DS2770  (3)
       DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)

   Counter
       DS2423 (3)

   LCD Screen
       LCD (3) DS2408 (3)

   Crypto
       DS1977 (3)

   Pressure
       DS2406 (3) -- TAI8570 EDS0066 (3) EDS0068 (3)

AVAILABILITY

       http://www.owfs.org

AUTHOR

       Paul Alfille (paul.alfille@gmail.com)