tc4(7)                          (RM400 only)                         tc4(7)

NAME
     tc4 - four port serial interface

DESCRIPTION
     There are currently two types of tc4 cards available for Reliant UNIX,
     each card contains four serial interfaces. The first tc4 supports four
     V24 interfaces, while the second tc4 supports four daughter boards
     which permit the card to support other interface standards. Both cards
     are handled identically by Reliant UNIX and a user can see no logical
     difference between the cards.

     Each Reliant UNIX system can normally support up to four tc4 cards,
     each serial channel has an associated logical device which is accessed
     through special files in the /dev/term directory.

     The tc4 is currently controlled through the sduart driver. The minor
     device numbers of the tc4 start at 80 and each card contains 4 logical
     devices, so that the first port on the first card has minor number 80,
     while the fourth port on the fourth card has minor number 111.

     At the moment, all serial devices controlled by the sduart driver
     automatically push the modules ldterm(7) and ttcompat(7)
     (/etc/ap/cons.ap).

     Each tc4 card contains four switches which determine the physical I/O
     address of the card, no two cards can have the same physical I/O
     address. The first logical card, is the card with the lowest physical
     I/O address, the next logical card is the card with the next higher
     physical I/O address etc. There need be no relationship between which
     slot the card is inserted in and the physical I/O address of the card.
     Reliant UNIX only uses the physical I/O address to differentiate
     between different cards.

   MODEM SIGNALS
     Each tc4 serial interface has three modem control lines. These are M1
     M5 and M2, M3 is NOT supported on the card. By default the driver
     responds to modem signals. If a logical device "X" is created which
     has a minor device number of "X" + 256, then all modem signals are
     ignored. Which modem signals are supported on each line can also be
     controlled on a per serial interface basis by the editing of the

     /etc/conf/pack.d/tc4/space.c

     file. If this file is edited, the kernel must be relinked and the sys-
     tem rebooted before the changes can take effect.










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tc4(7)                          (RM400 only)                         tc4(7)

     The driver supports the usual ioctls for a tty. Additionally, the
     driver handles the following ioctls with the form:

     ioctl (fd, ISTR, &arg)
     int fd
     struct strioctl arg

     The structure strioctl is defined in <stropts.h> and has to be filled
     in the following form:

     iccmd    = ioctl request (TIOCMODS, TIOCMODG, TIOCMGET)
     ictimout = 0
     iclen    = sizeof(int modemflags)
     icdp     = (char *)&modemflags

     modemflags

     0x00000001:   Modem signal M1 (DSR)
     0x00000002:   Modem signal M2 (CTS)
     0x00000004:   Modem signal M5 (DCD)

     TIOCMODS
          Sets the modem signals to be controlled by the driver (M1, M2,
          M3, M5) into modemflags.

     TIOCMODG
          Gets the current modem signals to be controlled by the driver.
          The driver sets the signals (flags) into modemflags.

     TIOCMGET
          The driver sets the current state of the modem signals into
          modemflags and returns the state to the user.

FILES
     /dev/term/{80-111}

     /dev/term/{336-367}

     /etc/conf/pack.d/tc4/space.c

     /etc/ap/cons.ap

SEE ALSO
     ldterm(7), termio(7), ttcompat(7).

     Programmer's Guide: STREAMS.








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