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diff --git a/Documentation/networking/baycom.txt b/Documentation/networking/baycom.txt deleted file mode 100644 index 688f18fd4467..000000000000 --- a/Documentation/networking/baycom.txt +++ /dev/null @@ -1,158 +0,0 @@ - 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 -separate drivers as they did not share any code, and the driver -and device names have changed. - -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, - 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, - however if you have a broken UART clone that does not have working - delta status bits, you may try baycom_ser_hdx. - -baycom_ser_hdx: - This is an alternative driver for SER12 type modems. - It only supports half duplex, and only 1200 baud. Its devices - are called bcsh0 through bcsh3. Use this driver only if baycom_ser_fdx - does not work with your UART. - -baycom_par: - This driver supports the par96 and picpar modems. - Its devices are called bcp0 through bcp3. - -baycom_epp: - This driver supports the EPP modem. - Its devices are called bce0 through bce3. - This driver is work-in-progress. - -The following modems are supported: - -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, - 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. The modem leaves the - 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 - 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. - - - -All of the above modems only support half duplex communications. However, -the driver supports the KISS (see below) fullduplex command. It then simply -starts to send as soon as there's a packet to transmit and does not care -about DCD, i.e. it starts to send even if there's someone else on the channel. -This command is required by some implementations of the DAMA channel -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 -simple. Once installed, four interfaces named bc{sf,sh,p,e}[0-3] are available. -sethdlc from the ax25 utilities may be used to set driver states etc. -Users of userland AX.25 stacks may use the net2kiss utility (also available -in the ax25 utilities package) to convert packets of a network interface -to a KISS stream on a pseudo tty. There's also a patch available from -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). - -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). - - insmod baycom_par mode="picpar" iobase=0x378 - sethdlc -i bcp0 -p mode "picpar" io 0x378 - -Both lines configure the first port to drive a picpar modem at the -first parallel port (LPT1 under DOS). (Note: picpar implies -hardware DCD, par96 implies software DCD). - -The channel access parameters can be set with sethdlc -a or kissparms. -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 - 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. - 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 - 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 -interface at a time. The serial driver grabs all interfaces it can find at -startup time. Therefore the baycom drivers subsequently won't be able to -access a serial port. You might therefore find it necessary to release -a port owned by the serial driver with 'setserial /dev/ttyS# uart none', where -# is the number of the interface. The baycom drivers do not reserve any -ports at startup, unless one is specified on the 'insmod' command line. Another -method to solve the problem is to compile all drivers as modules and -leave it to kmod to load the correct driver depending on the application. - -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 |