Provided by: freebsd-manpages_8.0-1_all bug

NAME

     digi - DigiBoard intelligent serial cards driver

SYNOPSIS

     device digi

     This man page was originally written for the dgb driver, and should
     likely be gone over with a fine tooth comb to reflect differences with
     the digi driver.

     When not defined the number is computed:

         default NDGBPORTS = number_of_described_DigiBoard_cards * 16

     If it is less than the actual number of ports the system will be able to
     use only the first NDGBPORTS ports.  If it is greater then all ports will
     be usable but some memory will be wasted.

     Meaning of flags:
     0x0001  use alternate pinout (exchange DCD and DSR lines)
     0x0002  do not use 8K window mode of PC/Xe

     Device numbering:
     0bCCmmmmmmmmOLIPPPPP
       CCard number
         mmmmmmmmajor number
                 callOut
                  Lock
                   Initial
                    PPPPPort number

DESCRIPTION

     The digi driver provides support for DigiBoard PC/Xe and PC/Xi series
     intelligent serial multiport cards with asynchronous interfaces based on
     the EIA RS-232C (CCITT V.24) standard.

     Input and output for each line may set to one of following baud rates;
     50, 75, 110, 134.5, 150, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200,
     38400, 57600, or for newer versions of cards 115200.

     The driver does not use any interrupts, it is “polling-based”.  This
     means that it uses clock interrupts instead of interrupts generated by
     DigiBoard cards and checks the state of cards 25 times per second.  This
     is practical because the DigiBoard cards have large input and output
     buffers (more than 1Kbyte per port) and hardware that allows efficiently
     finding the port that needs attention.  The only problem seen with this
     policy is slower SLIP and PPP response.

     Each line in the kernel configuration file describes one card, not one
     port as in the sio(4) driver.

     The flags keyword may be used on each “device dgb” line in the kernel
     configuration file to change the pinout of the interface or to use new
     PC/Xe cards which can work with an 8K memory window in compatibility mode
     (with a 64K memory window).  Note that using 8K memory window does not
     mean shorter input/output buffers, it means only that all buffers will be
     mapped to the same memory address and switched as needed.

     The port value must be the same as the port set on the card by jumpers.
     For PC/Xi cards the same rule is applicable to the iomem value.  It must
     be the same as the memory address set on the card by jumpers.  For PC/Xe
     cards there is no need to use jumpers for this purpose.  In fact there
     are no jumpers to do it.  Just write the address you want as the iomem
     value in kernel config file and the card will be programmed to use this
     address.

     The same range of memory addresses may be used for all the DigiBoards
     installed (but not for any other card or real memory).  DigiBoards with a
     large amount of memory (256K or 512K and perhaps even 128K) must be
     mapped to memory addresses outside of the first megabyte.  If the
     computer has more than 15 megabytes of memory then there is no free
     address space outside of the first megabyte where such DigiBoards can be
     mapped.  In this case you may need to reduce the amount of memory in the
     computer.  But many machines provide a better solution.  They have the
     ability to “turn off” the memory in the 16th megabyte (addresses 0xF00000
     - 0xFFFFFF) using the BIOS setup.  Then the DigiBoard’s address space can
     be set to this “hole”.

     Serial ports controlled by the digi driver can be used for both “callin”
     and “callout”.  For each port there is a callin device and a callout
     device.  The minor number of the callout device is 128 higher than that
     of the corresponding callin port.  The callin device is general purpose.
     Processes opening it normally wait for carrier and for the callout device
     to become inactive.  The callout device is used to steal the port from
     processes waiting for carrier on the callin device.  Processes opening it
     do not wait for carrier and put any processes waiting for carrier on the
     callin device into a deeper sleep so that they do not conflict with the
     callout session.  The callout device is abused for handling programs that
     are supposed to work on general ports and need to open the port without
     waiting but are too stupid to do so.

     The digi driver also supports an initial-state and a lock-state control
     device for each of the callin and the callout “data” devices.  The minor
     number of the initial-state device is 32 higher than that of the
     corresponding data device.  The minor number of the lock-state device is
     64 higher than that of the corresponding data device.  The termios
     settings of a data device are copied from those of the corresponding
     initial-state device on first opens and are not inherited from previous
     opens.  Use stty(1) in the normal way on the initial-state devices to
     program initial termios states suitable for your setup.

     The lock termios state acts as flags to disable changing the termios
     state.  E.g., to lock a flag variable such as CRTSCTS, use “stty crtscts”
     on the lock-state device.  Speeds and special characters may be locked by
     setting the corresponding value in the lock-state device to any nonzero
     value.

     Correct programs talking to correctly wired external devices work with
     almost arbitrary initial states and no locking, but other setups may
     benefit from changing some of the default initial state and locking the
     state.  In particular, the initial states for non (POSIX) standard flags
     should be set to suit the devices attached and may need to be locked to
     prevent buggy programs from changing them.  E.g., CRTSCTS should be
     locked on for devices that support RTS/CTS handshaking at all times and
     off for devices that do not support it at all.  CLOCAL should be locked
     on for devices that do not support carrier.  HUPCL may be locked off if
     you do not want to hang up for some reason.  In general, very bad things
     happen if something is locked to the wrong state, and things should not
     be locked for devices that support more than one setting.  The CLOCAL
     flag on callin ports should be locked off for logins to avoid certain
     security holes, but this needs to be done by getty if the callin port is
     used for anything else.

FILES

     /dev/ttyD??   for callin ports
     /dev/ttyiD??
     /dev/ttylD??  corresponding callin initial-state and lock-state devices

     /dev/cuaD??   for callout ports
     /dev/cuaiD??
     /dev/cualD??  corresponding callout initial-state and lock-state devices

     /etc/rc.serial  examples of setting the initial-state and lock-state
                     devices

     The first question mark in these device names is short for the card
     number (a decimal number between 0 and 65535 inclusive).  The second
     question mark is short for the port number (a letter in the range [0-9a-
     v]).

DIAGNOSTICS

     You may enable extended diagnostics by defining DEBUG at the start of the
     source file dgb.c.

     dgbX: warning: address N truncated to M  The memory address for the
     PC/Xe’s 8K window is misaligned (it should be on an 8K boundary) or
     outside of the first megabyte.

     dgbX: 1st reset failed  Problems with accessing I/O port of the card,
     probably the wrong port value is specified in the kernel config file.

     dgbX: 2nd reset failed  Problems with hardware.

     dgbX: N[st,nd,rd,th] memory test failed  Problems with accessing the
     memory of the card, probably the wrong iomem value is specified in the
     kernel config file.

     dgbX: BIOS start failed  Problems with starting the on-board BIOS.
     Probably the memory addresses of the DigiBoard overlap with some other
     device or with RAM.

     dgbX: BIOS download failed  Problems with the on-board BIOS.  Probably
     the memory addresses of the DigiBoard overlap with some other device or
     with RAM.

     dgbX: FEP code download failed  Problems with downloading of the Front-
     End Processor’s micro-OS.  Probably the memory addresses of the DigiBoard
     overlap with some other device or with RAM.

     dgbX: FEP/OS start failed  Problems with starting of the Front-End
     Processor’s micro-OS.  Probably the memory addresses of the DigiBoard
     overlap with some other device or with RAM.

     dgbX: too many ports  This DigiBoard reports that it has more than 32
     ports.  Perhaps a hardware problem or the memory addresses of the
     DigiBoard overlap with some other device or with RAM.

     dgbX: only N ports are usable  The NDGBPORTS parameter is too small and
     there is only enough space allocated for N ports on this card.

     dgbX: port Y is broken  The on-board diagnostic has reported that the
     specified port has hardware problems.

     dgbX: polling of disabled board stopped  Internal problems in the polling
     logic of driver.

     dgbX: event queues head or tail is wrong!  Internal problems in the
     driver or hardware.

     dgbX: port Y: got event on nonexisting port  Some status changed on a
     port that is physically present but is unusable due to misconfiguration.

     dgbX: port Y: event N mstat M lstat K  The driver got a strange event
     from card.  Probably this means that you have a newer card with an
     extended list of events or some other hardware problem.

     dgbX: port Y: overrun  Input buffer has filled up.  Problems in polling
     logic of driver.

     dgbX: port Y: FEP command on disabled port  Internal problems in driver.

     dgbX: port Y: timeout on FEP command  Problems in hardware.

SEE ALSO

     stty(1), termios(4), tty(4), comcontrol(8)

HISTORY

     The digi driver is derived from the sio(4) driver and the DigiBoard
     driver from Linux and is currently under development.

BUGS

     The implementation of sending BREAK is broken.  BREAK of fixed length of
     1/4 s is sent anyway.

     There was a bug in implementation of select(2).  It is fixed now but not
     widely tested yet.

     There is no ditty command.  Most of its functions (alternate pinout,
     speed up to 115200 baud, etc.) are implemented in the driver itself.
     Some other functions are missing.