cpt(7)                          (RM400 only)                         cpt(7)

NAME
     cpt, bcpt - Centronics interface control

DESCRIPTION
     /dev/cpt file is a special file that controls the Centronics interface
     for printers.

     /dev/bcpt file is a special file that controls the Centronics inter-
     face for printers in both directions (sending and receiving data).
     This interface conforms to IEEE 1284 and supports Compatibility Mode,
     Nibble Mode and Extended Capabilities Port (ECP) Mode. The mode is
     chosen automatically during negotiation phase, which is initiated
     after the open() system call to /dev/bcpt.

     Only one open() is permitted at a time for both devices. An open()
     system call to /dev/cpt or /dev/bcpt while one of these devices is
     already open will return with error EBUSY.

     If the printer device is powered down while transmitting data via the
     Centronics interface, the cpt driver sends a stream message MHANGUP
     to the streams head.

IOCTL
     Only one ioctl() is supported.

     TCSBRK The argument is an int value. Wait for the output to drain. If
            the argument is 0, then send a break (zero valued bits for 0.25
            seconds).

NOTES
     The device waits for the output to drain before it closes. If any
     error occurs, device will close after some time (cpt closes on paper
     empty!).

FILES
     /dev/cpt

     /dev/bcpt

SEE ALSO
     termio(7).














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