To compile the utilities, type
make dep ; make
It will make the following programs:
It will install these utilities in /sbin/ and an example configuration file as /etc/z8530drv.conf.ex. Rename this file to /etc/z8530drv.conf and edit it according to chapter 1.2. Please note that since version 3.0 of this driver the driver itself does not come with this package (hence the package name "z8530drv-*.*-utils.tar.gz").
Now configure the Linux kernel to prepare the compilation of the driver. If you are using menuconfig or xconfig select:
Do not forget to select other AX.25 devices you probably need, and do not forget to include the kernel AX.25 / NET/ROM / Rose stuff as well. Please read the AX25-HOWTO for details.
Save your new kernel configuration and either rebuild your kernel now (if you selected "Y" for CONFIG_SCC), or rebuild your modules (if you selected "M").
To use the driver, 3 steps must be performed:
Unlike the versions below 2.4 this driver is a real network device driver. If you want to run xNOS instead of our fine kernel AX.25 use a 2.x version (available from above sites) or read the AX.25-HOWTO on how to emulate a KISS TNC on network device drivers.
(If you're going to compile the driver as a part of the kernel image, skip this chapter and continue with 1.2)
Before you can use a module, you'll have to load it with
insmod scc
please read 'man insmod' that comes with modutils.
You should include the insmod in one of the /etc/rc.d/rc.* files, and don't forget to insert a call of sccinit after that. It will read your /etc/z8530drv.conf.
To set up all parameters you must run /sbin/sccinit from one of your rc.*-files. This has to be done BEFORE you can "ifconfig" an interface. Sccinit reads the file /etc/z8530drv.conf and sets the hardware, MODEM and KISS parameters. A sample file is delivered with this package. Change it to your needs.
The file itself consists of two main sections.
The hardware set-up section defines the following parameters for each Z8530:
chip 1 data_a 0x300 # data port A ctrl_a 0x304 # control port A data_b 0x301 # data port B ctrl_b 0x305 # control port B irq 5 # IRQ No. 5 pclock 4915200 # clock board BAYCOM # hardware type escc no # enhanced SCC chip? (8580/85180/85280) vector 0 # latch for interrupt vector special no # address of special function register option 0 # option to set via sfr
The config options are:
You can specify up to four chips (8 channels). If this is not enough, just change
#define MAXSCC 4
to a higher value.
chip 1 data_a 0x300 # data port A ctrl_a 0x304 # control port A data_b 0x301 # data port B ctrl_b 0x305 # control port B irq 5 # IRQ No. 5 (#) board BAYCOM # hardware type (*) # # SCC chip 2 # chip 2 data_a 0x302 ctrl_a 0x306 data_b 0x303 ctrl_b 0x307 board BAYCOM
chip 1 data_a 0x153 data_b 0x151 ctrl_a 0x152 ctrl_b 0x150 irq 9 pclock 4915200 board PA0HZP vector 0x168 escc no # # # chip 2 data_a 0x157 data_b 0x155 ctrl_a 0x156 ctrl_b 0x154 irq 9 pclock 4915200 board PA0HZP vector 0x168 escc no
chip 1 data_a 0x303 data_b 0x301 ctrl_a 0x302 ctrl_b 0x300 irq 7 pclock 4915200 board DRSI escc no # # # chip 2 data_a 0x313 data_b 0x311 ctrl_a 0x312 ctrl_b 0x310 irq 7 pclock 4915200 board DRSI escc no
Note that you cannot use the on-board baudrate generator off DRSI cards. Use "mode dpll" for clock source (see below). This is based on information provided by Mike Bilow (and verified by Paul Helay).
If you only know the parameters for the PE1CHL driver for DOS, run gencfg. It will generate the correct port addresses (I hope). Its parameters are exactly the same as the ones you use with the "attach scc" command in net, except that the string "init" must not appear. Example:
gencfg 2 0x150 4 2 0 1 0x168 9 4915200
will print a skeleton z8530drv.conf for the OptoSCC to stdout.
gencfg 2 0x300 2 4 5 -4 0 7 4915200 0x10
does the same for the BayCom USCC card. I my opinion it is much easier to edit scc_config.h...
The channel definition is divided into three sub sections for each channel:
An example for scc0:
# DEVICE
device scc0 # the device for the following params
# MODEM / BUFFERS
speed 1200 # the default baudrate
clock dpll # clock source:
# dpll = normal halfduplex operation
# external = MODEM provides own Rx/Tx clock
# divider = use fullduplex divider if
# installed (1)
mode nrzi # HDLC encoding mode
# nrzi = 1k2 MODEM, G3RUH 9k6 MODEM
# nrz = DF9IC 9k6 MODEM
#
bufsize 384 # size of buffers. Note that this must include
# the AX.25 header, not only the data field!
# (optional, defaults to 384)
# KISS (Layer 1)
txdelay 36 # (see chapter 1.4)
persist 64
slot 8
tail 8
fulldup 0
wait 12
min 3
maxkey 7
idle 3
maxdef 120
group 0
txoff off
softdcd on
slip off
The order within these sections is unimportant. The order of these sections is important. The MODEM parameters are set with the first recognized KISS parameter. Please note that you can initialize the board only once after boot (or insmod). You can change all parameters but "mode" and "clock" later with the Sccparam program or through KISS. Just to avoid security holes...
(1) this divider is usually mounted on the SCC board (PA0HZP) or not present at all (BayCom). It feeds back the output of the DPLL (digital pll) as transmit clock. Using this mode without a divider installed will normally result in keying the transceiver until maxkey expires, of course without sending anything (useful).
To set up an AX.25 device you can simply type:
ifconfig scc0 44.128.1.1 hw ax25 dl0tha-7
This will create a network interface with the IP number 44.128.20.107 and the callsign "dl0tha". If you do not have any IP number (yet) you can use any of the 44.128.0.0 network. Note that you do not need axattach. The purpose of axattach (like slattach) is to create a KISS network device linked to a TTY. Please read the documentation of the ax25-utils and the AX25-HOWTO to learn how to set the parameters of the kernel AX.25.
Since the TTY driver (aka KISS TNC emulation) is gone you need to emulate the old behaviour. The cost using these programs is that you probably need to compile the kernel AX.25, regardless if you actually use it or not. First set up your /etc/ax25/axports, for example:
9k6 dl0tha-9 9600 255 4 9600 baud port (scc3)
axlink dl0tha-15 38400 255 4 Link to NOS
Now "ifconfig" the scc device:
ifconfig scc3 44.128.1.1 hw ax25 dl0tha-9
You can now axattach a pseudo-TTY:
axattach /dev/ptys0 axlink
and start your NOS and attach /dev/ptys0 there. The problem is that NOS is reachable only via digipeating through the kernel AX.25 (disastrous on a DAMA controlled channel). To solve this problem, configure "rxecho" to echo the incoming frames from "9k6" to "axlink" and outgoing frames from "axlink" to "9k6" and start:
rxecho
Or simply use "kissbridge" coming with this package:
ifconfig scc3 hw ax25 dl0tha-9
kissbridge scc3 /dev/ptys0
There's a similar program called net2kiss coming with the AX.25 utilities which does basically the same (but the source looks better than mine...) and is better documented.
Once a SCC channel has been attached, the parameter settings and some statistic information can be shown using the param program:
dl1bke-u:~$ sccstat scc0 Parameters: speed : 1200 baud txdelay : 36 persist : 255 slottime : 0 txtail : 8 fulldup : 1 waittime : 12 mintime : 3 sec maxkeyup : 7 sec idletime : 3 sec maxdefer : 120 sec group : 0x00 txoff : off softdcd : on SLIP : off Status: HDLC Z8530 Interrupts Buffers ----------------------------------------------------------------------- Sent : 273 RxOver : 0 RxInts : 125074 Size : 384 Received : 1095 TxUnder: 0 TxInts : 4684 NoSpace : 0 RxErrors : 1591 ExInts : 11776 TxErrors : 0 SpInts : 1503 Tx State : idle
The status info shown is:
An overrun is abnormal. If lots of these occur, the product of baudrate and number of interfaces is too high for the processing power of you computer. NoSpace errors are not likely caused by the driver or the kernel AX.25.
The setting of parameters of the emulated KISS TNC is done in the same way in the SCC driver. You can change parameters by using the kissparms program from the ax25-utils package or use the program "sccparam":
sccparam <device> <paramname> <decimal | hexadecimal value>
You can change the following parameters:
Interfaces are in the same group, when the logical AND between their
xx values is not zero.
Examples: When 2 interfaces use group 201, their transmitters will never
be keyed at the same time. When 2 interfaces use group 101, the
transmitters will only key when both channels are clear at the same time.
When group 301, the transmitters will not be keyed at the same time.
Don't forget to convert the octal numbers into decimal before you set the
parameter.
Example: (still to be written)
If you have tx-problems with your BayCom USCC card please check the manufacturer of the 8530. SGS chips have a slightly different timing. Try Zilog... A solution is to write to register 8 instead to the data port, but this won't work with the ESCC chips. SIGH!
A very common problem is that the PTT locks until the maxkeyup timer expires, although interrupts and clock source are correct. In most cases #define SCC_DELAY solves the problems. For more hints read the (pseudo) FAQ and the documentation coming with z8530drv-utils.
I got reports that the driver has problems on some 386-based systems. (i.e. Amstrad) Those systems have a bogus AT bus timing which will lead to delayed answers on interrupts. You can recognize these problems by looking at the output of Sccstat for the suspected port. See if it shows under- and overruns you own such a system.
Delayed processing of received data:
This depends on
Kernel panics: please read to /linux/README and find out if it really occurred within the scc driver.
If you cannot solve a problem, send me
Mysteriously this board seems not to work with the driver. Anyone got it up-and-running?
The fullduplex mode 3 works as follows:
1. The protocol layer sends a KISS command
[PARAM_RTS] [TX_ON]
to key up the transmitter. Then it sends the data frame(s) to the driver. When all frames are sent, the driver will send the KISS command
[PARAM_HWEVENT] [HWEV_ALL_SENT].
The protocol layer may now key down the transmitter with
[PARAM_RTS] [TX_OFF]
or send more frames. Note that the maxkeyup timer may expire and key down the transceiver before everything is sent.
2. The driver sends
[PARAM_HWEVENT] [HWEV_DCD_ON] or
[PARAM_HWEVENT] [HWEV_DCD_OFF]
if the status of the DCD changes.
3. The protocol layer can send
[PARAM_HWEVENT] 0
the driver will reply with one of the DCD status messages.
Note that KISS command doesn't necessarily mean that the enclosed data is SLIP encoded. In network driver mode the driver does not encode/decode SLIP, but it will still distinguish between a data and a command packet by the leading byte, just like in 'real' KISS mode.
Note that this feature may vanish without a notice.
Many thanks to everyone who contributed to this project with ideas, error reports and bug fixes. Special thanks to Guido ten Dolle, PE1NNZ. Guido started the whole project in 1993, some of his code may be still in the current release...