NAME
hsq
—
multiplexing serial communications
interface
SYNOPSIS
hsq0 at isa? port 0x140 irq 10
com* at hsq?
DESCRIPTION
The hsq
driver provides support for
Hostess (Comtrol
Corporation) and compatible boards that multiplex together up to four
EIA RS-232C (CCITT V.28) communications interfaces.
Each hsq
device is the master device for
up to four com
devices. The kernel configuration
specifies these com
devices as slave devices of the
hsq
device, as shown in
SYNOPSIS. The slave ID given for each
com
device determines which bit in the interrupt
multiplexing register is tested to find interrupts for that device. The
port
specification for the
hsq
device is used to compute the base addresses for
the com
subdevices (they are equal to port + ID * 8)
and the port for the interrupt multiplexing register (it is equal to port +
7). More technical details on how the driver works can be found in the big
comment at the beginning of the driver's source code.
Information on setup of card's configuration switches should be taken from Comtrol Corporation's web site, since the author wrote and tested the driver only with Hostess-compatible cards.
FILES
- /dev/tty0?
- /dev/cua0?
SEE ALSO
HISTORY
The hsq
driver was written by
Denis A. Doroshenko based on the
ast(4) driver.