Baslinux mailing list

[sindi keesan <keesan AT sdf.lonestar.org>]

 >>
> > > is the modem internal? if so is it PCI? (if PCI thats your problem) if
> > > its ISA then disable onboard COM2 (ttyS1) and set the internal as com2
> > > (ttyS1)... if the modem is external and works fine with other systems

> > Is there a way to check the serial port in linux?  It works, just not very
> > consistently or fast.
>
> not unless you have something like statserial installed... a port
> tester from radioshack would be the second option...

statserial not found in SW7.1.  I found the source in .deb or .rpm form.
/usr/bin/rpm2targz from bin.tgz  or mc will extract a tar.gz from rpm, and 
ar -x from a deb format.

It probably needs a loopback connector.  We have one some place.
It shows the current state of various modem signal lines.
That might not diagnose one that is slow and discontinuous.

> i didnt mean to put windows there permanently... i ment to use it as a
> test to see what the hardware is doing...

I don't have a free partition with 200MB.  Or the time to waste on 
Windows installation.

Linux Serial HOWTO Jan 2007 290 KiB. 12.1  Serial Monitoring/Diagnostics 
Programs mentions statserial but there are no known diagnostic programs in 
linux for the serial port.

15. Troubleshooting mentions various gadgets designed for testing serial 
port lines, with connectors, voltmeter test points, LEDs, jumpers, 
switches, including Radio Shack RS-232 Troubleshooter.  It would be easier 
to diagnose something dead than intermittent.

There is a section on interrupt conflicts.  But there are no problems 
connecting at 14.4K, just at faster speeds.

To check if there is an interrupt problem use setserial to set IRQ to 0 
and use polling instead of interrupts.  Polling is not recommended because 
it is resource intensive.  But 'polling due to IRQ=0 is orders of 
magnitude faster than the slow "polling" due to bad interrupts".  This is 
a temporary fix.  I should check /proc/interrupts.  (I think I did but I 
am now using a different computer online).  Setserial can be wrong.

There is no pnp, just external modem on Com2.  No jumpers.  I set serial 
ports to either auto or manual standard settings.  I reserved IRQ3 for 
Com2 in BIOS.  Com1 is IRQ 4 and has a mouse - should I remove the mouse?
(A serial mini-trackball which syschk thought was a modem).

This 2001 board does not have a 16450 or 8250 UART.  16550.

I did a 'setserial -g ttyS*' on another computer and ttyS0 and S1 are 
16550A with correct address and IRQ.  S14 (which I made for a lucent modem 
that is not installed) is No such device.  And 2 3 and 4 are unknown. 
ttyS4 has IRQ 0.  Why do I have that device?

16.4 Interrupt Conflicts.  I don't think anything else uses IRQ 3.

> linux (BL or otherwise) doesnt ignore BIOS settings if the bios was
> written correctly (aka not an overly cheap OEM machine i810 fits this
> category) if you disable a serial port in the bios does it not
> disappear from BL?

I disabled Com2 in BIOS and I still find ttyS1 in dmesg as a 16550A - is 
this referring to the internal modem rather than the comport?

I think disabling onboard USB in BIOS also disabled it in linux.

I will reenable the sound chip in BIOS to test it.

> > See 'previous in thread' for the problem - slow connection which also
> > freezes up.
>
> that goes along with the serial port/modem/possible conflicts with
> other hardware... you said the ISP works fine with your other machines
> so it means either something is wrong with this machines hardware or
> something wasnt set right in software....

Probably hardware.

At least I have a repeatable test - 350-950 Byte/sec upload to shell 
account via kermit file transfer.


> > Sindi


> --sam
> --
> "When you've done something right, no one will be sure you've done
> anything at all." -- Futurama

It is not so clear when I have done something wrong.

Could the port have a damaged buffer? I can try com1 instead of com2.

Then set irq to 0 to use polling instead of interrupts as a test.
        setserial /dev/ttyS1 irq 0  (??)

Look for the serial loopback device.

Try an internal modem instead of a sound card.

Switch computers or use a slower one as a gateway.

Sindi