SEO

I use a NoHands Mouse with a serial interface. The regular mouse is a
PS/2, but I configured X Windows (via XF86Config) to use the serial
interface for the mouse instead.

This would otherwise be all fine and good, except that I have at least two
problems. (1) The mouse pointer jumps all over the place as I move it
with my foot (via the NoHands Mouse). (2) Also, my X Windows server
behaves strangely when using the serial port for the mouse verses the PS/2
mouse. The PS/2 mouse works perfectly, but, when using the serial mouse
interface, occassionally the entire X Windows server just freezes up and
stops until I move the mouse again. Even the keyboard doesn't work during
this time.

I was speculating that it might be the IRQ, but I used setserial to
examine /dev/ttyS1 and looked at /proc/interrupts and there were no
overlaps ('though I did notice that the serial device is not listed in
/proc/interrupts). I also checked /proc/ioports and it seemed
peachy-fine.

The baud rate is set at 1200 (by default, ttyS1 seems to go to 9600, but I
override it each time on boot).

BTW, I did disable gpm, but that didn't help. I haven't tried the
/dev/gpmdata trick.

The computer is running RedHat 9 with (I think) a 2.4.X kernel.

I'm sorry I can't dump out the output from setserial and the contents of
various /proc files, but the machine is at work and there is strict
network security there.

Thanks for any information.

["Followup-To:" header set to comp.os.linux.x.]
On 26 Aug 2004 14:35:07 -0500, Robert staggered into the Black Sun and
said:
> I use a NoHands Mouse with a serial interface. The regular mouse is a
> PS/2, but I configured X Windows (via XF86Config) to use the serial

"X" or "the X Window system", not "X Windows". Most folks just say "X".

> problems. (1) The mouse pointer jumps all over the place as I move it
> with my foot (via the NoHands Mouse). (2) Also, my X server behaves
> strangely when using the serial port for the mouse verses the PS/2
> mouse. The PS/2 mouse works perfectly, but, when using the serial
> mouse interface, occassionally the entire X server just freezes up and
> stops until I move the mouse again. Even the keyboard doesn't work
> during this time.

> I was speculating that it might be the IRQ, but I used setserial to
> examine /dev/ttyS1 and looked at /proc/interrupts and there were no
> overlaps ('though I did notice that the serial device is not listed in
> /proc/interrupts).

/dev/ttyS1 should use IRQ 3 (I think; it's been years since I've used a
serial device) and should be reported as doing so in /proc/interrupts.
Which protocol is the mouse set to? "Auto" often works with serial
mice, but there are exceptions. Post the relevant section from your
XF86Config file. Also look in /var/log/XFree86.0.log for any errors or
messages relating to the mouse. I've never tried to use a serial mouse
in X, but this behavior is atypical.

> The baud rate is set at 1200

Is this the only rate the mouse can handle? Mice aren't particularly
data-intensive, but it might work better at a higher speed.

> The computer is running RedHat 9 with (I think) a 2.4.X kernel.

The value of X is important. There are vast differences between a
2.4.26 (latest) and a 2.4.0 (first of the 2.4 series) kernel.
Everything before 2.4.10 was basically unusable for production (VM
problems, etcetera.)

> I'm sorry I can't dump out the output from setserial and the contents
> of various /proc files, but the machine is at work and there is strict
> network security there.

How annoying. Consult your company's Linux geek; if you don't have a
company Linux geek, see if the network admin can unbend for long enough
for you to copy the information down on paper and type it in later. The
only important bits of /proc/interrupts are IRQs 3 and 4, /proc/ioports
is not useful here, and the setserial stuff might be useful. The Mouse
sections of XF86Config and any mouse-related messages in
/var/log/XFree86.0.log would be really useful to see. HTH,

--
Matt G|There is no Darkness in Eternity/But only Light too dim for us to see
Brainbench MVP for Linux Admin / mail: TRAP + SPAN don't belong
http://www.brainbench.com / Hire me!
-----------------------------/ http://crow202.dyndns.org/~mhgraham/resume