dmf(4)dmf(4)Namedmf - DMF32 communications interface
Syntax
device dmf0 at uba? csr 0160340 flags 0x????
vector dmfsrint dmfsxint dmfdaint dmfdbint dmfrint dmfxint dmflint
Description
The device provides eight lines of asynchronous serial line support
with full modem control on two lines only. The device driver also
supports a connection to a line printer through the line printer port
of the DMF32.
Each line attached to a DMF32 serial line port behaves as described in
Input and output for each line can be set independently to run at any
of 16 speeds. See for the encoding.
Bit i of can be specified for a to say that a line is not properly con‐
nected, and that the line should be treated as hardwired, with carrier
always present. Thus, specifying ``flags 0x00f6'' in the specification
of would cause lines 0 and 1 on the DMF32 to be treated as modem lines,
while lines 2 through 7 are direct connect no-modem lines. It is
important to specify lines 2 through 7 as direct connect, because the
device does not support modem control on these lines.
The driver normally uses input silos and polls for input at each clock
tick (10 milliseconds). The DMF32 will discard incoming characters on
the lines with full modem control, if carrier is not present.
Restrictions
The DMF32 provides other services, but these are not supported by the
driver.
Diagnostics
dmf%d: NXM line %d
No response from UNIBUS on a transfer within a timeout period. This is
often followed by a UNIBUS adapter error. This occurs most frequently
when the UNIBUS is heavily loaded and when devices that monopolize the
bus, such as RK07s, are present. It is not serious.
dmf%d: silo overflow
The 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 then prints a message on the console with
interrupts disabled.
dmfsrint
dmfsxint
dmfdaint
dmfdbint
One of the unsupported ports of the DMF32 interrupted because of a
problem. Check your interrupt vectors for a conflict with another
device.
Files
(modem lines only)
See Alsodmfsp(4), tty(4), MAKEDEV(8)
VAX dmf(4)
