Serial Mouse Problem
Forum: Other Help Topics
Topic: Serial Mouse Problem
started by: minuscule
Posted by minuscule on Jan. 09 2004,23:10
I am trying to run DSL 0.5.1.1 on a machine with a single serial port(COM1, 0x3F8, IRQ 4). This same machine and mouse works fine in Win98SE. When booting, DSL says “Mouse is Generic Serial Mouse at /dev/ttyS0”. But both in X and in links, the mouse does not work. If I try cat /dev/ttyS0, I get “ttyS0: LSR safety check engaged!”(that wise mouse won't be fooled by no stinking cat... 
) If I boot with Coyote Linux from a floppy and try again cat /dev/ttyS0 I get the expected flow of non-sense characters each time I move the mouse.So it seems that DSL 0.5.1.1 does like my mouse or UART. Any idea?
Posted by cbagger01 on Jan. 10 2004,00:09
Try the search button above and search for keyword "mouse", search all message boards and search "From the beginning" instead of "last month".I think that there is some previous discussion on the issue that involves changing your xsetup file.
Posted by minuscule on Jan. 13 2004,03:00
It took me quite some time to find the solution to make the mouse work. I was about to give up when I decided to test systematically all serial port configurations with 2 mice plugged in the 2 serial ports at the back of the computer. I was able to dig out a DB-9 to DB-25 adapter and an extra mouse in what I used to call my black hole of dusty crap but that I am going to rename my treasure trove from now on. Here are the results(hope that my clumsy table will be rendered correctly in your browser):
BIOS Serial 1 | BIOS Serial 2 | DSL behavior | Coyote Linux | Notes
-----------------------------------------------------------------------------------------
COM1/3F8 | disabled | ttyS0 <-> none | ttyS0 <-> DB9 |
COM3/3E8 | disabled | ttyS2 <-> DB25 | ttyS2 <-> DB9 | DSL needs 2 mice to make one work!!!
COM4/2E8 | disabled | ttyS3 <-> DB9 | ttyS3 <-> DB9 |
disabled | COM2/2F8 | ttyS1 <-> none | ttyS1 <-> DB25 |
disabled | COM3/3E8 | ttyS2 <-> DB25 | ttyS2 <-> DB25 |
disabled | COM4/2E8 | ttyS3 <-> DB9 | ttyS3 <-> DB25 | DSL needs 2 mice to make one work!!!
Coyote Linux is a one floppy firewall distribution that I happen to have. It provided a quick way of seeing the behavior of another Linux distribution.
As you can see, DSL has a quite weird behavior on my hardware.
From these results, we can say:
1) COM1 and COM2 can not be used.
2) BIOS serial 1 COM3 gets magically rerouted to the DB25 connector but we still need a mouse connected to the DB9 so that DSL can detect a serial mouse when booting.
2) BIOS serial 2 COM4 gets magically rerouted to the DB9 connector but we still need a mouse connected to the DB25 so that DSL can detect a serial mouse when booting.
4) Only BIOS serial 1 set as COM4 and BIOS serial 2 set as COM3 behave as expected.
Maybe, all this is a specific interaction between my hardware and/or BIOS with DSL. If others want to experiment with serial mice to see if they can reproduce these results.
BTW, is it normal that /etc/X11/XF86Config is totally ignored by X? I spent some time tweaking this file when I realized that whatever I put in there, it was not taken into account by X.
Posted by cbagger01 on Jan. 13 2004,03:15
DSL uses the KDrive "TinyX" Xserver instead of the standard Xfree86 Xserver. This means that many (if not all) of the Xwindows configuration is done by the command line inside the xsetup shell script file that is created by the Xwindows startup menu (config script is named xsetup.sh) This 'xsetup.sh' script then creates the 'xsetup' file based on how you answer the questions.There may be a portion of the Xf86Config file that is actually used by the Kdrive XVesa or Xfbdev servers but on the surface it looks like the file is pretty meaningless to me.
So if you want to make a serial mouse work with Xwindows, all you should need to do is:
Hit CTRL-ALT-BACKSPACE to exit Xwindows.
open xsetup via the nano editor IE: nano xsetup
change /dev/psaux to your serial port where the mouse is located (/dev/ttyS3?)
Save the file
type 'startx' to relaunch xwindows.
The autodetect messages look nice on the screen, but I doubt that this info is used by the Kdrive server.Hope this helps.
Posted by minuscule on Jan. 13 2004,06:09
Note that a generic way would be to specify /dev/mouse instead since this symbolic link points automatically to the ttySx where a serial mouse was detected. Note also that /dev/psaux is in xsetup only when one selects the PS/2 wheel mouse when running xsetup.sh.Having said that, whether I have -mouse /dev/mouse or not in xsetup(BTW, I also tried /dev/ttyS3), it does not make any difference: the only settings where I can use a serial mouse on my DB9 connector is to set the BIOS serial 1 to COM4.
I am afraid the mystery is still unsolved...
I reiterate my invitation to people who have a serial mouse to see if they get the same results as me. I suspect that my BIOS is fooling DSL about the serial ports.
bye