[nSLUG] Hardware modem not detected by Ubuntu 5.04/ 2.6 kernel

Rich budman85 at eastlink.ca
Fri Mar 31 19:07:48 AST 2006

On Fri, 2006-03-31 at 17:29 -0400, Jeff 'n Joan wrote:
> Thanks for the reply Rich. 
> I couldn't find a file(or anything similar) called serial.conf in /etc
> on my RH9 distro.
> Typing grep -r tty* in terminal as root just causes terminal to hang( it
> doesn't do anything and doesn't return to prompt.
> I was hoping to see what RH9 said so I could make Ubuntu do the same.
> I didn't load Ubuntu to try your suggestions since it takes so long to
> install and then reinstall RH9 when it doesn't work.
> Perhaps I'll wait until the June Installfest and let someone take a
> crack at it. Hopefully I won't miss this one.
> Jeff

There was a space between the tty and * (-r tells it recursively search
	grep -r tty *

I wasn't thinking last night, I forgot I had a RH9 machine running.

Looks like redhat turns serial detection off by adding safe=no
to /etc/sysconfig/kudzu

Change it to anything other than  safe=no

As for ubuntu, I found some notes, it uses /etc/serial.conf

try  setserial -g 

you can either edit the serial.conf to enable the serial port
since your red hat boot showed the base address as 0x03e8
the problem you may have is IRQ 4:
	COM1 & 3 share the same IRQ
	COM2 & 4 share the same IRQ

If you pc has 2 serial ports, pick a new IRQ.
Try 5 or 10  ( check /proc/interrupts to see whats assigned)

You can use setserial to enable it without rebooting.

setserial /dev/ttyS2 irq 5 port 0x03e8

add this line to /etc/serial.conf
/dev/ttyS2 uart 16450 port 0x3E8 irq 5

see if serial module is loaded
	lsmod | grep serial

Give that a shot.


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