dmf(4)
NAME
dmf − DMF32 communications interface
SYNTAX
device dmf0 at uba? csr 0160340 flags 0x????
vector dmfsrint dmfsxint dmfdaint dmfdbint dmfrint dmfxint dmflint
DESCRIPTION
The dmf 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 tty(.). Input and output for each line may independently be set to run at any of 16 speeds. See tty() for the encoding.
Bit i of flags may be specified for a dmf to say that a line is not properly connected, and that the line should be treated as hardwired with carrier always present. Thus specifying “flags 0x0004” in the specification of dmf0 would cause line 2 on the DMF32 to be treated in this way.
The dmf driver normally uses input silos and polls for input at each clock tick (10 milliseconds).
CAUTION
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 dma 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 will then print 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
/dev/tty??
/dev/ttyd?(modem lines only)