[plug] Serial port fun

[John Breen]

On Sun, 29 Apr 2001, Kai wrote:
> ----- Original Message -----
> From: "John Breen" <wombat at redback.apana.org.au>
> To: <plug at plug.linux.org.au>
> Sent: Sunday, April 29, 2001 7:16 PM
> Subject: Re: [plug] Serial port fun
> 
> 
> > On Sun, 29 Apr 2001, Kai wrote:
> > > The 4 port serial card should've come with some doco, right?
> > Doco....
> >
> > That's that piece of paper, right?
> 
> Yeah, the card should have come with some sort of documentation so you know
> how to configure it.

Yup - I read it before I changed any jumper settings.  In fact it's sitting
here now and I've checked it.

> 
> > > More than likely need to run cat /proc/pci and see where the addresses
> are
> > > so you can get Linux to see the ports and use them.
> >
> > Oops, my fault - like many people it seems I didn't give enough details in
> the
> > first place...
> >
> > It's a jumpered card (not Shrug 'n' Pray), and it's ISA.
> 
> what about cat /proc/interrupts ?

ah, that may be worth a look - when I set the machine up tomorrow :)

Apart from IRQ15 being used by the IDE secondary controller, it looks right
though.

> 
> > We plugged in the card, did a kernel compile with extended serial support,
> (for
> > more than 4 ports) and rebooted.  No sign of the ports.  After much
> hunting
> > around, we did a mknod to get 4 devices to show up.  So far so hoopy.
> Then we
> > did setserial for each of the ports (like this)
> > # setserial /dev/ttyS4 irq 15 uart 16550
> > # setserial /dev/ttyS5 irq 12 uart 16550
> > # setserial /dev/ttyS6 irq 10 uart 16550
> > # setserial /dev/ttyS7 irq 9 uart 16550
> 
> I think the card will have some sort documentation to show you how to
> configure it !

as i said, yup - read it.  for each port, there's two jumpers.  one sets the
i/o address (or the COM port number).  the other sets the IRQ.

> 
> > now, ignoring the obvious IRQ conflicts here, that says that the first
> port is
> > COM4 with an IRQ of 14, the second COM5 with IRQ 12 and so on.  Am I
> right?
> 
> Did you check in setserial (man setserial I think) for the commonly used
> IRQ's for existing processes?

Ya, it just said don't use numbers other than 2(9), 3, 4, 5, 7, 9, 10, 11, 12
and 15.

Still, I'll just keep muddling along with it.  Sometimes I hate jumpered cards,
but I find they tend to be a little more trouble-free once they're working :)

 -- 
Regards,

John Breen

+----------------------------------------------------+
| John Breen                                         |
| Contracting Delphi Developer                       |
+----------------------------------------------------+
| Ph (08) 9430-4003                                  |
| wombat at redback.apana.org.au - john at fairport.com.au |
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