ZS(4) | Device Drivers Manual (sgi) | ZS(4) |
zs
, zskbd
,
zsms
, zstty
—
Zilog 8530 (ZSCC) Serial Communications
Controller
zs0 at hpc0
zs1 at hpc0
zskbd* at zs1 channel 0
(Indigo)
zsms* at zs1 channel 1
(Indigo)
zstty* at zs0 channel ?
The zs
driver provides TTY support for
Zilog 8530 Dual UART chips. On Indigo systems, one of the interfaces is
hardwired for use by the keyboard and mouse. The
zskbd
devices connect keyboard devices to the
generic keyboard driver wskbd
. The
zsms
devices connect mice to the generic mouse
driver wsmouse(4). The
remaining additional zstty
interfaces provide RS-423
and RS-232 serial ports for general purpose use.
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.
Input and output for each line may set to any baud rate in the range 50 to 38400 (and higher on some machines).
On some systems, the hardware design causes the state of the CTS,
DCD, DTR and RTS lines to be inverted. While the
zstty
driver attempts to correctly account for this
quirk, it can be forced to reverse its logic by setting
flags to 1 (either via
config(8) or
boot_config(8)).
Misconfiguration of these line settings usually leads to
getty(8) processes being
unable to open the device or sleeping on
‘ttyopn
’.
May 12, 2012 | OpenBSD-6.9 |