rc(4) RISCom/8 multiport card


device isa device rc


The RISCom/8 is an eight port ISA RS-232C communications multiplexer with a built in RISC processor. It uses a block of sixteen I/O ports in the range 0x200 to 0x3f0 selectable by on-board switches or jumpers. The block must be aligned on a sixteen port boundary. The jumper-selectable hardware interrupt level may be set to be detected during system initialization using settings found in the /boot/device.hints file.

This driver is mostly based on the Cirrus Logic CL-CD180 driver.


The driver provides support for the SDL Communications RISCom/8 boards.


The following driver specific error messages may be reported:

"rc%d channel%d: interrupt-level buffer overflow"
An internal buffer overflow error has occurred on the listed channel. The driver will need to be reloaded to correct this.
"rc%d: Bad char chan %d"
The channel has obtained a bad set of characters.
"rc%d: Got extra chars chan %d"
The driver got more characters than expected on the channel shown.
"rc%d: data mismatch chan %d ptr %d (%d != %d)"
Data sent from channel %d to the rx buffer was different then expected.
"rc%d: channel %d command timeout, rc.c line: %d"
A command timeout has occurred on the channel, the src/sys/dev/rc/rc.c file can be consulted for more information.


The driver first appeared in Fx 2.0.5 . This manual page first appeared in Fx 5.3 .


This manual page was written by An Tom Rhodes Aq [email protected] .


The driver code still uses the spl(9) functions. These should be replaced by mutex(9) functions.

The various Fn ttyld_* functions should be documented.