ZS(4) - Device Drivers Manual (macppc) #
ZS(4) - Device Drivers Manual (macppc)
NAME #
zs, zstty - Zilog 8530 (ZSCC) serial communications driver
SYNOPSIS #
zs* at macobio? zstty* at zs?
DESCRIPTION #
The
zs
is a Zilog 8530 serial interface chip used in
Sun
workstations and
Apple
Macintosh systems.
On most newer Macintosh systems, the first port
tty00
is connected to the internal modem.
The second port is either not connected, or may be connected to
an IRDA device (untested).
It is possible to replace the internal modem on some system with
a real serial port using third party hardware adapters.
The zs driver supports all of the standard tty(4) ioctl calls. The status of the DTR, RTS, CTS, and DCD signals can be queried with TIOCMGET command, but, due to limitations in the hardware, only the DTR and RTS signals can be modified with TIOCMSET, TIOCMBIC, and TIOCMBIS ioctl(2) commands.
FILES #
/dev/tty00
/dev/tty01
/dev/cua00
/dev/cua01
SEE ALSO #
HISTORY #
The zs driver first appeared in 4.4BSD. Support for the TIOCM* ioctl(2)s appeared in OpenBSD 2.3.
BUGS #
The zs driver now supports cua minor devices, but with this known deficiency in the simultaneous outgoing/incoming aspect of the driver: The first outgoing connection succeeds, but second and subsequent connections fail, apparently due to a getty hang. The hung getty apparently prevents the cua device from being re-opened.
OpenBSD 7.5 - November 23, 2015