384 lines
15 KiB
Plaintext
384 lines
15 KiB
Plaintext
|
|
specialix.txt -- specialix IO8+ multiport serial driver readme.
|
|
|
|
|
|
|
|
Copyright (C) 1997 Roger Wolff (R.E.Wolff@BitWizard.nl)
|
|
|
|
Specialix pays for the development and support of this driver.
|
|
Please DO contact io8-linux@specialix.co.uk if you require
|
|
support.
|
|
|
|
This driver was developed in the BitWizard linux device
|
|
driver service. If you require a linux device driver for your
|
|
product, please contact devices@BitWizard.nl for a quote.
|
|
|
|
This code is firmly based on the riscom/8 serial driver,
|
|
written by Dmitry Gorodchanin. The specialix IO8+ card
|
|
programming information was obtained from the CL-CD1865 Data
|
|
Book, and Specialix document number 6200059: IO8+ Hardware
|
|
Functional Specification, augmented by document number 6200088:
|
|
Merak Hardware Functional Specification. (IO8+/PCI is also
|
|
called Merak)
|
|
|
|
|
|
This program is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU General Public License as
|
|
published by the Free Software Foundation; either version 2 of
|
|
the License, or (at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be
|
|
useful, but WITHOUT ANY WARRANTY; without even the implied
|
|
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
|
|
PURPOSE. See the GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public
|
|
License along with this program; if not, write to the Free
|
|
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
|
|
USA.
|
|
|
|
|
|
Intro
|
|
=====
|
|
|
|
|
|
This file contains some random information, that I like to have online
|
|
instead of in a manual that can get lost. Ever misplace your Linux
|
|
kernel sources? And the manual of one of the boards in your computer?
|
|
|
|
|
|
Addresses and interrupts
|
|
========================
|
|
|
|
Address dip switch settings:
|
|
The dip switch sets bits 2-9 of the IO address.
|
|
|
|
9 8 7 6 5 4 3 2
|
|
+-----------------+
|
|
0 | X X X X X X X |
|
|
| | = IoBase = 0x100
|
|
1 | X |
|
|
+-----------------+ ------ RS232 connectors ---->
|
|
|
|
| | |
|
|
edge connector
|
|
| | |
|
|
V V V
|
|
|
|
Base address 0x100 caused a conflict in one of my computers once. I
|
|
haven't the foggiest why. My Specialix card is now at 0x180. My
|
|
other computer runs just fine with the Specialix card at 0x100....
|
|
The card occupies 4 addresses, but actually only two are really used.
|
|
|
|
The PCI version doesn't have any dip switches. The BIOS assigns
|
|
an IO address.
|
|
|
|
The driver now still autoprobes at 0x100, 0x180, 0x250 and 0x260. If
|
|
that causes trouble for you, please report that. I'll remove
|
|
autoprobing then.
|
|
|
|
The driver will tell the card what IRQ to use, so you don't have to
|
|
change any jumpers to change the IRQ. Just use a command line
|
|
argument (irq=xx) to the insmod program to set the interrupt.
|
|
|
|
The BIOS assigns the IRQ on the PCI version. You have no say in what
|
|
IRQ to use in that case.
|
|
|
|
If your specialix cards are not at the default locations, you can use
|
|
the kernel command line argument "specialix=io0,irq0,io1,irq1...".
|
|
Here "io0" is the io address for the first card, and "irq0" is the
|
|
irq line that the first card should use. And so on.
|
|
|
|
Examples.
|
|
|
|
You use the driver as a module and have three cards at 0x100, 0x250
|
|
and 0x180. And some way or another you want them detected in that
|
|
order. Moreover irq 12 is taken (e.g. by your PS/2 mouse).
|
|
|
|
insmod specialix.o iobase=0x100,0x250,0x180 irq=9,11,15
|
|
|
|
The same three cards, but now in the kernel would require you to
|
|
add
|
|
|
|
specialix=0x100,9,0x250,11,0x180,15
|
|
|
|
to the command line. This would become
|
|
|
|
append="specialix=0x100,9,0x250,11,0x180,15"
|
|
|
|
in your /etc/lilo.conf file if you use lilo.
|
|
|
|
The Specialix driver is slightly odd: It allows you to have the second
|
|
or third card detected without having a first card. This has
|
|
advantages and disadvantages. A slot that isn't filled by an ISA card,
|
|
might be filled if a PCI card is detected. Thus if you have an ISA
|
|
card at 0x250 and a PCI card, you would get:
|
|
|
|
sx0: specialix IO8+ Board at 0x100 not found.
|
|
sx1: specialix IO8+ Board at 0x180 not found.
|
|
sx2: specialix IO8+ board detected at 0x250, IRQ 12, CD1865 Rev. B.
|
|
sx3: specialix IO8+ Board at 0x260 not found.
|
|
sx0: specialix IO8+ board detected at 0xd800, IRQ 9, CD1865 Rev. B.
|
|
|
|
This would happen if you don't give any probe hints to the driver.
|
|
If you would specify:
|
|
|
|
specialix=0x250,11
|
|
|
|
you'd get the following messages:
|
|
|
|
sx0: specialix IO8+ board detected at 0x250, IRQ 11, CD1865 Rev. B.
|
|
sx1: specialix IO8+ board detected at 0xd800, IRQ 9, CD1865 Rev. B.
|
|
|
|
ISA probing is aborted after the IO address you gave is exhausted, and
|
|
the PCI card is now detected as the second card. The ISA card is now
|
|
also forced to IRQ11....
|
|
|
|
|
|
Baud rates
|
|
==========
|
|
|
|
The rev 1.2 and below boards use a CL-CD1864. These chips can only
|
|
do 64kbit. The rev 1.3 and newer boards use a CL-CD1865. These chips
|
|
are officially capable of 115k2.
|
|
|
|
The Specialix card uses a 25MHz crystal (in times two mode, which in
|
|
fact is a divided by two mode). This is not enough to reach the rated
|
|
115k2 on all ports at the same time. With this clock rate you can only
|
|
do 37% of this rate. This means that at 115k2 on all ports you are
|
|
going to lose characters (The chip cannot handle that many incoming
|
|
bits at this clock rate.) (Yes, you read that correctly: there is a
|
|
limit to the number of -=bits=- per second that the chip can handle.)
|
|
|
|
If you near the "limit" you will first start to see a graceful
|
|
degradation in that the chip cannot keep the transmitter busy at all
|
|
times. However with a central clock this slow, you can also get it to
|
|
miss incoming characters. The driver will print a warning message when
|
|
you are outside the official specs. The messages usually show up in
|
|
the file /var/log/messages .
|
|
|
|
The specialix card cannot reliably do 115k2. If you use it, you have
|
|
to do "extensive testing" (*) to verify if it actually works.
|
|
|
|
When "mgetty" communicates with my modem at 115k2 it reports:
|
|
got: +++[0d]ATQ0V1H0[0d][0d][8a]O[cb][0d][8a]
|
|
^^^^ ^^^^ ^^^^
|
|
|
|
The three characters that have the "^^^" under them have suffered a
|
|
bit error in the highest bit. In conclusion: I've tested it, and found
|
|
that it simply DOESN'T work for me. I also suspect that this is also
|
|
caused by the baud rate being just a little bit out of tune.
|
|
|
|
I upgraded the crystal to 66Mhz on one of my Specialix cards. Works
|
|
great! Contact me for details. (Voids warranty, requires a steady hand
|
|
and more such restrictions....)
|
|
|
|
|
|
(*) Cirrus logic CD1864 databook, page 40.
|
|
|
|
|
|
Cables for the Specialix IO8+
|
|
=============================
|
|
|
|
The pinout of the connectors on the IO8+ is:
|
|
|
|
pin short direction long name
|
|
name
|
|
Pin 1 DCD input Data Carrier Detect
|
|
Pin 2 RXD input Receive
|
|
Pin 3 DTR/RTS output Data Terminal Ready/Ready To Send
|
|
Pin 4 GND - Ground
|
|
Pin 5 TXD output Transmit
|
|
Pin 6 CTS input Clear To Send
|
|
|
|
|
|
-- 6 5 4 3 2 1 --
|
|
| |
|
|
| |
|
|
| |
|
|
| |
|
|
+----- -----+
|
|
|__________|
|
|
clip
|
|
|
|
Front view of an RJ12 connector. Cable moves "into" the paper.
|
|
(the plug is ready to plug into your mouth this way...)
|
|
|
|
|
|
NULL cable. I don't know who is going to use these except for
|
|
testing purposes, but I tested the cards with this cable. (It
|
|
took quite a while to figure out, so I'm not going to delete
|
|
it. So there! :-)
|
|
|
|
|
|
This end goes This end needs
|
|
straight into the some twists in
|
|
RJ12 plug. the wiring.
|
|
IO8+ RJ12 IO8+ RJ12
|
|
1 DCD white -
|
|
- - 1 DCD
|
|
2 RXD black 5 TXD
|
|
3 DTR/RTS red 6 CTS
|
|
4 GND green 4 GND
|
|
5 TXD yellow 2 RXD
|
|
6 CTS blue 3 DTR/RTS
|
|
|
|
|
|
Same NULL cable, but now sorted on the second column.
|
|
|
|
1 DCD white -
|
|
- - 1 DCD
|
|
5 TXD yellow 2 RXD
|
|
6 CTS blue 3 DTR/RTS
|
|
4 GND green 4 GND
|
|
2 RXD black 5 TXD
|
|
3 DTR/RTS red 6 CTS
|
|
|
|
|
|
|
|
This is a modem cable usable for hardware handshaking:
|
|
RJ12 DB25 DB9
|
|
1 DCD white 8 DCD 1 DCD
|
|
2 RXD black 3 RXD 2 RXD
|
|
3 DTR/RTS red 4 RTS 7 RTS
|
|
4 GND green 7 GND 5 GND
|
|
5 TXD yellow 2 TXD 3 TXD
|
|
6 CTS blue 5 CTS 8 CTS
|
|
+---- 6 DSR 6 DSR
|
|
+---- 20 DTR 4 DTR
|
|
|
|
This is a modem cable usable for software handshaking:
|
|
It allows you to reset the modem using the DTR ioctls.
|
|
I (REW) have never tested this, "but xxxxxxxxxxxxx
|
|
says that it works." If you test this, please
|
|
tell me and I'll fill in your name on the xxx's.
|
|
|
|
RJ12 DB25 DB9
|
|
1 DCD white 8 DCD 1 DCD
|
|
2 RXD black 3 RXD 2 RXD
|
|
3 DTR/RTS red 20 DTR 4 DTR
|
|
4 GND green 7 GND 5 GND
|
|
5 TXD yellow 2 TXD 3 TXD
|
|
6 CTS blue 5 CTS 8 CTS
|
|
+---- 6 DSR 6 DSR
|
|
+---- 4 RTS 7 RTS
|
|
|
|
I bought a 6 wire flat cable. It was colored as indicated.
|
|
Check that yours is the same before you trust me on this.
|
|
|
|
|
|
Hardware handshaking issues.
|
|
============================
|
|
|
|
The driver can be told to operate in two different ways. The default
|
|
behaviour is specialix.sx_rtscts = 0 where the pin behaves as DTR when
|
|
hardware handshaking is off. It behaves as the RTS hardware
|
|
handshaking signal when hardware handshaking is selected.
|
|
|
|
When you use this, you have to use the appropriate cable. The
|
|
cable will either be compatible with hardware handshaking or with
|
|
software handshaking. So switching on the fly is not really an
|
|
option.
|
|
|
|
I actually prefer to use the "specialix.sx_rtscts=1" option.
|
|
This makes the DTR/RTS pin always an RTS pin, and ioctls to
|
|
change DTR are always ignored. I have a cable that is configured
|
|
for this.
|
|
|
|
|
|
Ports and devices
|
|
=================
|
|
|
|
Port 0 is the one furthest from the card-edge connector.
|
|
|
|
Devices:
|
|
|
|
You should make the devices as follows:
|
|
|
|
bash
|
|
cd /dev
|
|
for i in 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 \
|
|
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
|
|
do
|
|
echo -n "$i "
|
|
mknod /dev/ttyW$i c 75 $i
|
|
mknod /dev/cuw$i c 76 $i
|
|
done
|
|
echo ""
|
|
|
|
If your system doesn't come with these devices preinstalled, bug your
|
|
linux-vendor about this. They have had ample time to get this
|
|
implemented by now.
|
|
|
|
You cannot have more than 4 boards in one computer. The card only
|
|
supports 4 different interrupts. If you really want this, contact me
|
|
about this and I'll give you a few tips (requires soldering iron)....
|
|
|
|
If you have enough PCI slots, you can probably use more than 4 PCI
|
|
versions of the card though....
|
|
|
|
The PCI version of the card cannot adhere to the mechanical part of
|
|
the PCI spec because the 8 serial connectors are simply too large. If
|
|
it doesn't fit in your computer, bring back the card.
|
|
|
|
|
|
------------------------------------------------------------------------
|
|
|
|
|
|
Fixed bugs and restrictions:
|
|
- During initialization, interrupts are blindly turned on.
|
|
Having a shadow variable would cause an extra memory
|
|
access on every IO instruction.
|
|
- The interrupt (on the card) should be disabled when we
|
|
don't allocate the Linux end of the interrupt. This allows
|
|
a different driver/card to use it while all ports are not in
|
|
use..... (a la standard serial port)
|
|
== An extra _off variant of the sx_in and sx_out macros are
|
|
now available. They don't set the interrupt enable bit.
|
|
These are used during initialization. Normal operation uses
|
|
the old variant which enables the interrupt line.
|
|
- RTS/DTR issue needs to be implemented according to
|
|
specialix' spec.
|
|
I kind of like the "determinism" of the current
|
|
implementation. Compile time flag?
|
|
== Ok. Compile time flag! Default is how Specialix likes it.
|
|
== Now a config time flag! Gets saved in your config file. Neat!
|
|
- Can you set the IO address from the lilo command line?
|
|
If you need this, bug me about it, I'll make it.
|
|
== Hah! No bugging needed. Fixed! :-)
|
|
- Cirrus logic hasn't gotten back to me yet why the CD1865 can
|
|
and the CD1864 can't do 115k2. I suspect that this is
|
|
because the CD1864 is not rated for 33MHz operation.
|
|
Therefore the CD1864 versions of the card can't do 115k2 on
|
|
all ports just like the CD1865 versions. The driver does
|
|
not block 115k2 on CD1864 cards.
|
|
== I called the Cirrus Logic representative here in Holland.
|
|
The CD1864 databook is identical to the CD1865 databook,
|
|
except for an extra warning at the end. Similar Bit errors
|
|
have been observed in testing at 115k2 on both an 1865 and
|
|
a 1864 chip. I see no reason why I would prohibit 115k2 on
|
|
1864 chips and not do it on 1865 chips. Actually there is
|
|
reason to prohibit it on BOTH chips. I print a warning.
|
|
If you use 115k2, you're on your own.
|
|
- A spiky CD may send spurious HUPs. Also in CLOCAL???
|
|
-- A fix for this turned out to be counter productive.
|
|
Different fix? Current behaviour is acceptable?
|
|
-- Maybe the current implementation is correct. If anybody
|
|
gets bitten by this, please report, and it will get fixed.
|
|
|
|
-- Testing revealed that when in CLOCAL, the problem doesn't
|
|
occur. As warned for in the CD1865 manual, the chip may
|
|
send modem intr's on a spike. We could filter those out,
|
|
but that would be a cludge anyway (You'd still risk getting
|
|
a spurious HUP when two spikes occur.).....
|
|
|
|
|
|
|
|
Bugs & restrictions:
|
|
- This is a difficult card to autoprobe.
|
|
You have to WRITE to the address register to even
|
|
read-probe a CD186x register. Disable autodetection?
|
|
-- Specialix: any suggestions?
|
|
|
|
|