NAME
dz —
DZ-11 multiplexer device
interface
SYNOPSIS
dz0 at uba0 csr 0160100
dz0 at vsbus0 csr 0x200a0000 (DC-367)
dz0 at vsbus0 csr 0x25000000 (VS4000/90 4000/10x
MV3100/9x)
dz* at fwio? (VAXstation 35x0 and 38x0)
lkkbd0 at dz0 line 0
lkms0 at dz0 line 1
DESCRIPTION
A DZ-11 provides 4 or 8 communication lines with partial modem control, adequate for OpenBSD dialup use.
Normal I/O control parameters for individual lines are managed by ioctl(2) calls. Line speeds may be initiated via the ttys(5) file or stty(1), see tty(4).
The dz driver monitors the rate of input
on each board, and switches between the use of character-at-a-time
interrupts and input silos. While the silo is enabled during periods of
high-speed input, the driver polls for input 30 times per second.
On VAXstation systems, lines 0 and 1 are tied to the keyboard and
mouse connectors, which are driven by the lkkbd and
lkms drivers, respectively.
FILES
- /dev/tty0[0-7]
- dialups
DIAGNOSTICS
- dz0: silo overflow.
- The 64 character input silo overflowed before it could be serviced. This can happen if a hard error occurs when the CPU is running with elevated priority, as the system will then print a message on the console with interrupts disabled. It is not serious.
SEE ALSO
HISTORY
A dz driver appeared in
Version 7 AT&T UNIX/32V.