Commit b5fcf32d authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by David S. Miller
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docs: networking: convert baycom.txt to ReST 



- add SPDX header;
- adjust titles and chapters, adding proper markups;
- mark code blocks and literals as such;
- mark tables as such;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 20b943f0

Documentation/networking/baycom.txt→Documentation/networking/baycom.rst

+68 −52
Original line number Diff line number Diff line 
		    LINUX DRIVERS FOR BAYCOM MODEMS

.. SPDX-License-Identifier: GPL-2.0



===============================

Linux Drivers for Baycom Modems

===============================



Thomas M. Sailer, HB9JNX/AE4WA, <sailer@ife.ee.ethz.ch>



!!NEW!! (04/98) The drivers for the baycom modems have been split into

The drivers for the baycom modems have been split into

separate drivers as they did not share any code, and the driver

and device names have changed.
@@ -10,10 +14,11 @@ This document describes the Linux Kernel Drivers for simple Baycom style 
amateur radio modems.



The following drivers are available:

====================================



baycom_ser_fdx:

  This driver supports the SER12 modems either full or half duplex.

  Its baud rate may be changed via the `baud' module parameter,

  Its baud rate may be changed via the ``baud`` module parameter,

  therefore it supports just about every bit bang modem on a

  serial port. Its devices are called bcsf0 through bcsf3.

  This is the recommended driver for SER12 type modems,
@@ -37,7 +42,8 @@ baycom_epp: 


The following modems are supported:



ser12:  This is a very simple 1200 baud AFSK modem. The modem consists only

======= ========================================================================

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, as well as

	for handling the HDLC protocol. The modem connects to a serial port,
@@ -45,7 +51,7 @@ ser12: This is a very simple 1200 baud AFSK modem. The modem consists only 
	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.

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.
@@ -54,18 +60,19 @@ par96: This is a modem for 9600 baud FSK compatible to the G3RUH standard. 
	implementation of the HDLC protocol and the scrambler polynomial to

	the PC.



picpar: This is a redesign of the par96 modem by Henning Rech, DF9IC. The modem

picpar  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. Furthermore, it incorporates a carrier

	detect circuitry.



EPP:    This is a high-speed modem adaptor that connects to an enhanced parallel port.

        Its target audience is users working over a high speed hub (76.8kbit/s).



eppfpga: This is a redesign of the EPP adaptor.

EPP     This is a high-speed modem adaptor that connects to an enhanced parallel

	port.



	Its target audience is users working over a high speed hub (76.8kbit/s).



eppfpga This is a redesign of the EPP adaptor.

======= ========================================================================



All of the above modems only support half duplex communications. However,

the driver supports the KISS (see below) fullduplex command. It then simply
@@ -76,6 +83,7 @@ access protocol. 




The Interface of the drivers

============================



Unlike previous drivers, these drivers are no longer character devices,

but they are now true kernel network interfaces. Installation is therefore
@@ -88,20 +96,22 @@ me for WAMPES which allows attaching a kernel network interface directly. 




Configuring the driver

======================



Every time a driver is inserted into the kernel, it has to know which

modems it should access at which ports. This can be done with the setbaycom

utility. If you are only using one modem, you can also configure the

driver from the insmod command line (or by means of an option line in

/etc/modprobe.d/*.conf).

``/etc/modprobe.d/*.conf``).



Examples::



Examples:

  modprobe baycom_ser_fdx mode="ser12*" iobase=0x3f8 irq=4

  sethdlc -i bcsf0 -p mode "ser12*" io 0x3f8 irq 4



Both lines configure the first port to drive a ser12 modem at the first

serial port (COM1 under DOS). The * in the mode parameter instructs the driver to use

the software DCD algorithm (see below).

serial port (COM1 under DOS). The * in the mode parameter instructs the driver

to use the software DCD algorithm (see below)::



  insmod baycom_par mode="picpar" iobase=0x378

  sethdlc -i bcp0 -p mode "picpar" io 0x378
@@ -115,29 +125,33 @@ Note that both utilities interpret the values slightly differently. 




Hardware DCD versus Software DCD

================================



To avoid collisions on the air, the driver must know when the channel is

busy. This is the task of the DCD circuitry/software. The driver may either

utilise a software DCD algorithm (options=1) or use a DCD signal from

the hardware (options=0).



ser12:  if software DCD is utilised, the radio's squelch should always be

======= =================================================================

ser12   if software DCD is utilised, the radio's squelch should always be

	open. It is highly recommended to use the software DCD algorithm,

	as it is much faster than most hardware squelch circuitry. The

	disadvantage is a slightly higher load on the system.



par96:  the software DCD algorithm for this type of modem is rather poor.

par96   the software DCD algorithm for this type of modem is rather poor.

	The modem simply does not provide enough information to implement

	a reasonable DCD algorithm in software. Therefore, if your radio

	feeds the DCD input of the PAR96 modem, the use of the hardware

	DCD circuitry is recommended.



picpar: the picpar modem features a builtin DCD hardware, which is highly

picpar  the picpar modem features a builtin DCD hardware, which is highly

	recommended.

======= =================================================================







Compatibility with the rest of the Linux kernel

===============================================



The serial driver and the baycom serial drivers compete

for the same hardware resources. Of course only one driver can access a given
@@ -154,5 +168,7 @@ The parallel port drivers (baycom_par, baycom_epp) now use the parport subsystem 
to arbitrate the ports between different client drivers.



vy 73s de



Tom Sailer, sailer@ife.ee.ethz.ch



hb9jnx @ hb9w.ampr.org

Documentation/networking/index.rst

+1 −0
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@@ -43,6 +43,7 @@ Contents: 
   arcnet

   atm

   ax25

   baycom



.. only::  subproject and html

drivers/net/hamradio/Kconfig

+4 −4
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@@ -127,7 +127,7 @@ config BAYCOM_SER_FDX 
	  your serial interface chip. To configure the driver, use the sethdlc

	  utility available in the standard ax25 utilities package. For

	  information on the modems, see <http://www.baycom.de/> and

	  <file:Documentation/networking/baycom.txt>.

	  <file:Documentation/networking/baycom.rst>.



	  To compile this driver as a module, choose M here: the module

	  will be called baycom_ser_fdx.  This is recommended.
@@ -145,7 +145,7 @@ config BAYCOM_SER_HDX 
	  the driver, use the sethdlc utility available in the standard ax25

	  utilities package. For information on the modems, see

	  <http://www.baycom.de/> and

	  <file:Documentation/networking/baycom.txt>.

	  <file:Documentation/networking/baycom.rst>.



	  To compile this driver as a module, choose M here: the module

	  will be called baycom_ser_hdx.  This is recommended.
@@ -160,7 +160,7 @@ config BAYCOM_PAR 
	  par96 designs. To configure the driver, use the sethdlc utility

	  available in the standard ax25 utilities package. For information on

	  the modems, see <http://www.baycom.de/> and the file

	  <file:Documentation/networking/baycom.txt>.

	  <file:Documentation/networking/baycom.rst>.



	  To compile this driver as a module, choose M here: the module

	  will be called baycom_par.  This is recommended.
@@ -175,7 +175,7 @@ config BAYCOM_EPP 
	  designs. To configure the driver, use the sethdlc utility available

	  in the standard ax25 utilities package. For information on the

	  modems, see <http://www.baycom.de/> and the file

	  <file:Documentation/networking/baycom.txt>.

	  <file:Documentation/networking/baycom.rst>.



	  To compile this driver as a module, choose M here: the module

	  will be called baycom_epp.  This is recommended.