CONS(4)

NAME
cons - Sequent console interface

SYNOPSIS
device co0 at sec? doneq 10 req 10 bin 4 unit 0 # input
device co0 at sec? doneq 10 req 10 bin 4 unit 1 # output

device sc0 at ssm? bin 4 unit 0 # local
device sc1 at ssm? bin 4 unit 1 # remote

DESCRIPTION
The Sequent console interface provides access to the system console through a Sequent SCSI/Ethernet/Diagnostics (SCED) Board or Sequent System Services Module (SSM), depending on which board has taken control of the system during boot. (If an SSM is present in a system, it will provide the console interface, even though a SCED board may also be present in the system. If no SSM is present, the SCED board will provide the console interface.)

The co driver provides the SCED console interface functionality. Similarly, the sc driver provides the SSM console interface functionality.

When DYNIX is running, the interface behaves like a normal DYNIX terminal; see tty(4). Two terminal lines are available per SCED or SSM. All standard baud rates are supported on each of these lines. The hardware signals DTR and RTS are enabled on open of the lines and disabled on close. These signals may be changed via ioctl calls to the device driver and are used when flow control is enabled. Break character detection and generation is also supported.

An additional special file named /dev/console tracks the line selected by the monitor firmware as the console device. The line selected as console can be accessed from either the file /dev/console or the corresponding /dev/ttyc[0-7] or /dev/ttyb[0-7] name. Thus, there are two names for that terminal line.

A SCED console line selected as console gets default erase, kill, and interrupt characters from the monitor firmware settings for that line. In addition, if the SCED monitor firmware flags specify that break characters cause a return to monitor firmware, a break on the console line will cause an immediate return to firmware. Otherwise, the break character is interpreted according to tty(4).

Other than these exceptions, the console works like any other DYNIX terminal.

DIAGNOSTICS
SCED console diagnostic messages:

se%d: console device not binary configured. If a console device was not specified in the conf/conf_co.c file, this message appears at boot time.

co: stray interrupt, unit out of range %x. An interrupt was received on a unit which was not configured. The interrupt is ignored.

co: stray interrupt, dead unit %x. An interrupt was received on a unit which was previously determined to be not functional. The interrupt is ignored.

SSM console diagnostic messages:

sc:%d stray interrupt, unit out of range. An interrupt was received on a unit that was not configured. The interrupt is ignored.

sc%d: stray interrupt, dead unit. An interrupt was received on a unit that was previously determined to be nonfunctional. The interrupt is ignored.

sc%d: spurious interrupt received. An interrupt was received from a unit for an SSM transfer that had not yet completed. The interrupt is ignored and the transfer is allowed to complete.

sc: no memory for state info pointers. An attempt to allocate memory for the driver failed.

sc: no memory for info structure. An attempt to allocate memory for the driver failed.

sc: no memory for tty structure. An attempt to allocate memory for the driver failed.

sc: Warning! No /dev/console configured. No SSM console port was found that was designated as /dev/console.

MINOR NUMBERS
Minor numbers for device nodes corresponding to console lines are selected as follows:

    device	minor number	location
    /dev/ttyc0	0	SCED Board 0, local port
    /dev/ttyc1	1	SCED Board 0, remote port
    /dev/ttyc2	2	SCED Board 1, local port
    /dev/ttyc3	3	SCED Board 1, remote port
    /dev/ttyc4	4	SCED Board 2, local port
    /dev/ttyc5	5	SCED Board 2, remote port
    /dev/ttyc6	6	SCED Board 3, local port
    /dev/ttyc7	7	SCED Board 3, remote port
    /dev/ttyb0	0	SSM Board 0, local port
    /dev/ttyb1	1	SSM Board 0, remote port
    /dev/ttyb2	2	SSM Board 1, local port
    /dev/ttyb3	3	SSM Board 1, remote port
    /dev/ttyb4	4	SSM Board 2, local port
    /dev/ttyb5	5	SSM Board 2, remote port
    /dev/ttyb6	6	SSM Board 3, local port
    /dev/ttyb7	7	SSM Board 3, remote port
    /dev/console	64	(current console)

FILES
/dev/console
/dev/ttyc[0-7]
/dev/ttyb[0-7]
/sys/conf/conf_co.c
/sys/conf/conf_sc.c

SEE ALSO
tty(4)

BUGS
SCED modem control does not work properly. DTR and RTS always reflect the monitor firmware flags on a SCED-based system.

The SCED transmit break ioctl function does not work.

There are some SCED flow control problems. Data can be lost on transmit to another host because the local machine does not respond to flow control properly.

The SCED monitor firmware erase, kill, interrupt characters are not inherited when returning to single user operation from multiuser operation.