mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-29 15:43:59 +08:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
658 lines
20 KiB
Plaintext
658 lines
20 KiB
Plaintext
This is a subset of the documentation. To use this driver you MUST have the
|
|
full package from:
|
|
|
|
Internet:
|
|
=========
|
|
|
|
1. ftp://ftp.ccac.rwth-aachen.de/pub/jr/z8530drv-utils_3.0-3.tar.gz
|
|
|
|
2. ftp://ftp.pspt.fi/pub/ham/linux/ax25/z8530drv-utils_3.0-3.tar.gz
|
|
|
|
Please note that the information in this document may be hopelessly outdated.
|
|
A new version of the documentation, along with links to other important
|
|
Linux Kernel AX.25 documentation and programs, is available on
|
|
http://yaina.de/jreuter
|
|
|
|
-----------------------------------------------------------------------------
|
|
|
|
|
|
SCC.C - Linux driver for Z8530 based HDLC cards for AX.25
|
|
|
|
********************************************************************
|
|
|
|
(c) 1993,2000 by Joerg Reuter DL1BKE <jreuter@yaina.de>
|
|
|
|
portions (c) 1993 Guido ten Dolle PE1NNZ
|
|
|
|
for the complete copyright notice see >> Copying.Z8530DRV <<
|
|
|
|
********************************************************************
|
|
|
|
|
|
1. Initialization of the driver
|
|
===============================
|
|
|
|
To use the driver, 3 steps must be performed:
|
|
|
|
1. if compiled as module: loading the module
|
|
2. Setup of hardware, MODEM and KISS parameters with sccinit
|
|
3. Attach each channel to the Linux kernel AX.25 with "ifconfig"
|
|
|
|
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.
|
|
|
|
|
|
1.1 Loading the module
|
|
======================
|
|
|
|
(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.o
|
|
|
|
please read 'man insmod' that comes with module-init-tools.
|
|
|
|
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.
|
|
|
|
1.2. /etc/z8530drv.conf
|
|
=======================
|
|
|
|
To setup 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.
|
|
|
|
1.2.1 configuration of hardware parameters
|
|
==========================================
|
|
|
|
The hardware setup 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
|
|
|
|
|
|
chip - this is just a delimiter to make sccinit a bit simpler to
|
|
program. A parameter has no effect.
|
|
|
|
data_a - the address of the data port A of this Z8530 (needed)
|
|
ctrl_a - the address of the control port A (needed)
|
|
data_b - the address of the data port B (needed)
|
|
ctrl_b - the address of the control port B (needed)
|
|
|
|
irq - the used IRQ for this chip. Different chips can use different
|
|
IRQs or the same. If they share an interrupt, it needs to be
|
|
specified within one chip-definition only.
|
|
|
|
pclock - the clock at the PCLK pin of the Z8530 (option, 4915200 is
|
|
default), measured in Hertz
|
|
|
|
board - the "type" of the board:
|
|
|
|
SCC type value
|
|
---------------------------------
|
|
PA0HZP SCC card PA0HZP
|
|
EAGLE card EAGLE
|
|
PC100 card PC100
|
|
PRIMUS-PC (DG9BL) card PRIMUS
|
|
BayCom (U)SCC card BAYCOM
|
|
|
|
escc - if you want support for ESCC chips (8580, 85180, 85280), set
|
|
this to "yes" (option, defaults to "no")
|
|
|
|
vector - address of the vector latch (aka "intack port") for PA0HZP
|
|
cards. There can be only one vector latch for all chips!
|
|
(option, defaults to 0)
|
|
|
|
special - address of the special function register on several cards.
|
|
(option, defaults to 0)
|
|
|
|
option - The value you write into that register (option, default is 0)
|
|
|
|
You can specify up to four chips (8 channels). If this is not enough,
|
|
just change
|
|
|
|
#define MAXSCC 4
|
|
|
|
to a higher value.
|
|
|
|
Example for the BAYCOM USCC:
|
|
----------------------------
|
|
|
|
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
|
|
|
|
An example for a PA0HZP card:
|
|
-----------------------------
|
|
|
|
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
|
|
|
|
A DRSI would should probably work with this:
|
|
--------------------------------------------
|
|
(actually: two DRSI cards...)
|
|
|
|
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)
|
|
|
|
The utility "gencfg"
|
|
--------------------
|
|
|
|
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. In my opinion it is much easier
|
|
to edit scc_config.h...
|
|
|
|
|
|
1.2.2 channel configuration
|
|
===========================
|
|
|
|
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 half duplex operation
|
|
# external = MODEM provides own Rx/Tx clock
|
|
# divider = use full duplex 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-PBC (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).
|
|
|
|
2. Attachment of a channel by your AX.25 software
|
|
=================================================
|
|
|
|
2.1 Kernel AX.25
|
|
================
|
|
|
|
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 AX.25-HOWTO to learn how to set the parameters of
|
|
the kernel AX.25.
|
|
|
|
2.2 NOS, NET and TFKISS
|
|
=======================
|
|
|
|
Since the TTY driver (aka KISS TNC emulation) is gone you need
|
|
to emulate the old behaviour. The cost of using these programs is
|
|
that you probably need to compile the kernel AX.25, regardless of whether
|
|
you actually use it or not. First setup 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 z8530drv-utils:
|
|
|
|
ifconfig scc3 hw ax25 dl0tha-9
|
|
kissbridge scc3 /dev/ptys0
|
|
|
|
|
|
3. Adjustment and Display of parameters
|
|
=======================================
|
|
|
|
3.1 Displaying SCC Parameters:
|
|
==============================
|
|
|
|
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:
|
|
|
|
Sent - number of frames transmitted
|
|
Received - number of frames received
|
|
RxErrors - number of receive errors (CRC, ABORT)
|
|
TxErrors - number of discarded Tx frames (due to various reasons)
|
|
Tx State - status of the Tx interrupt handler: idle/busy/active/tail (2)
|
|
RxOver - number of receiver overruns
|
|
TxUnder - number of transmitter underruns
|
|
RxInts - number of receiver interrupts
|
|
TxInts - number of transmitter interrupts
|
|
EpInts - number of receiver special condition interrupts
|
|
SpInts - number of external/status interrupts
|
|
Size - maximum size of an AX.25 frame (*with* AX.25 headers!)
|
|
NoSpace - number of times a buffer could not get allocated
|
|
|
|
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 your computer. NoSpace errors are unlikely to be caused by the
|
|
driver or the kernel AX.25.
|
|
|
|
|
|
3.2 Setting Parameters
|
|
======================
|
|
|
|
|
|
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:
|
|
|
|
param : value
|
|
------------------------
|
|
speed : 1200
|
|
txdelay : 36
|
|
persist : 255
|
|
slottime : 0
|
|
txtail : 8
|
|
fulldup : 1
|
|
waittime : 12
|
|
mintime : 3
|
|
maxkeyup : 7
|
|
idletime : 3
|
|
maxdefer : 120
|
|
group : 0x00
|
|
txoff : off
|
|
softdcd : on
|
|
SLIP : off
|
|
|
|
|
|
The parameters have the following meaning:
|
|
|
|
speed:
|
|
The baudrate on this channel in bits/sec
|
|
|
|
Example: sccparam /dev/scc3 speed 9600
|
|
|
|
txdelay:
|
|
The delay (in units of 10 ms) after keying of the
|
|
transmitter, until the first byte is sent. This is usually
|
|
called "TXDELAY" in a TNC. When 0 is specified, the driver
|
|
will just wait until the CTS signal is asserted. This
|
|
assumes the presence of a timer or other circuitry in the
|
|
MODEM and/or transmitter, that asserts CTS when the
|
|
transmitter is ready for data.
|
|
A normal value of this parameter is 30-36.
|
|
|
|
Example: sccparam /dev/scc0 txd 20
|
|
|
|
persist:
|
|
This is the probability that the transmitter will be keyed
|
|
when the channel is found to be free. It is a value from 0
|
|
to 255, and the probability is (value+1)/256. The value
|
|
should be somewhere near 50-60, and should be lowered when
|
|
the channel is used more heavily.
|
|
|
|
Example: sccparam /dev/scc2 persist 20
|
|
|
|
slottime:
|
|
This is the time between samples of the channel. It is
|
|
expressed in units of 10 ms. About 200-300 ms (value 20-30)
|
|
seems to be a good value.
|
|
|
|
Example: sccparam /dev/scc0 slot 20
|
|
|
|
tail:
|
|
The time the transmitter will remain keyed after the last
|
|
byte of a packet has been transferred to the SCC. This is
|
|
necessary because the CRC and a flag still have to leave the
|
|
SCC before the transmitter is keyed down. The value depends
|
|
on the baudrate selected. A few character times should be
|
|
sufficient, e.g. 40ms at 1200 baud. (value 4)
|
|
The value of this parameter is in 10 ms units.
|
|
|
|
Example: sccparam /dev/scc2 4
|
|
|
|
full:
|
|
The full-duplex mode switch. This can be one of the following
|
|
values:
|
|
|
|
0: The interface will operate in CSMA mode (the normal
|
|
half-duplex packet radio operation)
|
|
1: Fullduplex mode, i.e. the transmitter will be keyed at
|
|
any time, without checking the received carrier. It
|
|
will be unkeyed when there are no packets to be sent.
|
|
2: Like 1, but the transmitter will remain keyed, also
|
|
when there are no packets to be sent. Flags will be
|
|
sent in that case, until a timeout (parameter 10)
|
|
occurs.
|
|
|
|
Example: sccparam /dev/scc0 fulldup off
|
|
|
|
wait:
|
|
The initial waittime before any transmit attempt, after the
|
|
frame has been queue for transmit. This is the length of
|
|
the first slot in CSMA mode. In full duplex modes it is
|
|
set to 0 for maximum performance.
|
|
The value of this parameter is in 10 ms units.
|
|
|
|
Example: sccparam /dev/scc1 wait 4
|
|
|
|
maxkey:
|
|
The maximal time the transmitter will be keyed to send
|
|
packets, in seconds. This can be useful on busy CSMA
|
|
channels, to avoid "getting a bad reputation" when you are
|
|
generating a lot of traffic. After the specified time has
|
|
elapsed, no new frame will be started. Instead, the trans-
|
|
mitter will be switched off for a specified time (parameter
|
|
min), and then the selected algorithm for keyup will be
|
|
started again.
|
|
The value 0 as well as "off" will disable this feature,
|
|
and allow infinite transmission time.
|
|
|
|
Example: sccparam /dev/scc0 maxk 20
|
|
|
|
min:
|
|
This is the time the transmitter will be switched off when
|
|
the maximum transmission time is exceeded.
|
|
|
|
Example: sccparam /dev/scc3 min 10
|
|
|
|
idle
|
|
This parameter specifies the maximum idle time in full duplex
|
|
2 mode, in seconds. When no frames have been sent for this
|
|
time, the transmitter will be keyed down. A value of 0 is
|
|
has same result as the fullduplex mode 1. This parameter
|
|
can be disabled.
|
|
|
|
Example: sccparam /dev/scc2 idle off # transmit forever
|
|
|
|
maxdefer
|
|
This is the maximum time (in seconds) to wait for a free channel
|
|
to send. When this timer expires the transmitter will be keyed
|
|
IMMEDIATELY. If you love to get trouble with other users you
|
|
should set this to a very low value ;-)
|
|
|
|
Example: sccparam /dev/scc0 maxdefer 240 # 2 minutes
|
|
|
|
|
|
txoff:
|
|
When this parameter has the value 0, the transmission of packets
|
|
is enable. Otherwise it is disabled.
|
|
|
|
Example: sccparam /dev/scc2 txoff on
|
|
|
|
group:
|
|
It is possible to build special radio equipment to use more than
|
|
one frequency on the same band, e.g. using several receivers and
|
|
only one transmitter that can be switched between frequencies.
|
|
Also, you can connect several radios that are active on the same
|
|
band. In these cases, it is not possible, or not a good idea, to
|
|
transmit on more than one frequency. The SCC driver provides a
|
|
method to lock transmitters on different interfaces, using the
|
|
"param <interface> group <x>" command. This will only work when
|
|
you are using CSMA mode (parameter full = 0).
|
|
The number <x> must be 0 if you want no group restrictions, and
|
|
can be computed as follows to create restricted groups:
|
|
<x> is the sum of some OCTAL numbers:
|
|
|
|
200 This transmitter will only be keyed when all other
|
|
transmitters in the group are off.
|
|
100 This transmitter will only be keyed when the carrier
|
|
detect of all other interfaces in the group is off.
|
|
0xx A byte that can be used to define different groups.
|
|
Interfaces are in the same group, when the logical AND
|
|
between their xx values is nonzero.
|
|
|
|
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: (to be written)
|
|
|
|
softdcd:
|
|
use a software dcd instead of the real one... Useful for a very
|
|
slow squelch.
|
|
|
|
Example: sccparam /dev/scc0 soft on
|
|
|
|
|
|
4. Problems
|
|
===========
|
|
|
|
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 compiling the driver with CONFIG_SCC_DELAY (set with
|
|
make config) 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. If it shows under- and overruns you own such a system.
|
|
|
|
Delayed processing of received data: This depends on
|
|
|
|
- the kernel version
|
|
|
|
- kernel profiling compiled or not
|
|
|
|
- a high interrupt load
|
|
|
|
- a high load of the machine --- running X, Xmorph, XV and Povray,
|
|
while compiling the kernel... hmm ... even with 32 MB RAM ... ;-)
|
|
Or running a named for the whole .ampr.org domain on an 8 MB
|
|
box...
|
|
|
|
- using information from rxecho or kissbridge.
|
|
|
|
Kernel panics: please read /linux/README and find out if it
|
|
really occurred within the scc driver.
|
|
|
|
If you cannot solve a problem, send me
|
|
|
|
- a description of the problem,
|
|
- information on your hardware (computer system, scc board, modem)
|
|
- your kernel version
|
|
- the output of cat /proc/net/z8530
|
|
|
|
4. Thor RLC100
|
|
==============
|
|
|
|
Mysteriously this board seems not to work with the driver. Anyone
|
|
got it up-and-running?
|
|
|
|
|
|
Many thanks to Linus Torvalds and Alan Cox for including the driver
|
|
in the Linux standard distribution and their support.
|
|
|
|
Joerg Reuter ampr-net: dl1bke@db0pra.ampr.org
|
|
AX-25 : DL1BKE @ DB0ABH.#BAY.DEU.EU
|
|
Internet: jreuter@yaina.de
|
|
WWW : http://yaina.de/jreuter
|