NAME
baycom - amateur (AX.25) packet radio network driver for baycom modems
SYNOPSIS
#include <linux/baycom.h>
#include <linux/hdlcdrv.h>
DESCRIPTION
The driver currently supports three different modems: ser12, par96 and
par97.
ser12
This is a very simple 1200 baud AFSK modem. The modem consists only of
a modulator/demodulator chip, usually a TI TCM3105. The computer is
responsible for regenerating the receiver bit clock. The modem connects
to a serial port, hence the name. Since the serial port is not used as
an async serial port, the kernel driver for serial ports cannot be
used, and this driver only supports standard serial hardware (8250,
16450, 16550).
par96
This is a modem for 9600 baud FSK compatible to the G3RUH standard.
The modem does all the filtering and regenerates the receiver clock.
Data is transferred from and to the PC via a shift register. The shift
register is filled with 16 bits and an interrupt is signalled. The PC
then empties the shift register in a burst. This modem connects to the
parallel port, hence the name.
par97
This is a redesign of the par96 modem by Henning Rech, DF9IC. The modem
is protocol compatible to par96, but uses only three low power ICs and
can therefore be fed from the parallel port and does not require an
additional power supply.
IOCTL CALLS
The ioctl calls follow the implementation in the hdlcdrv.
BAYCOMCTL_GETMODEMTYPE
returns the modem type (i.e. ser12 or par96) and the options in
effect (currently only the source of the DCD signal)
BAYCOMCTL_SETMODEMTYPE
sets the modem type and the options. Only superuser can do this.
BAYCOMCTL_GETDEBUG
return some debugging values. Not always available.
SEE ALSO
baycom (9), soundmodem (9), linux/drivers/net/hdlcdrv.c,
AUTHOR
baycom was written by Thomas Sailer, HB9JNX/AE4WA,
(sailer@ife.ee.ethz.ch).