Zilog 8530 (ZSCC) serial communications driver
zs* at macobio?
zstty* at zs?
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.
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
zs driver first appeared in
4.4BSD. Support for the TIOCM*
ioctl(2)s appeared in
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.