Subject: Second serial port (was Re: sligthly confused)
To: NetBSD port-arm32 <port-arm32@NetBSD.ORG>
From: Mark Brinicombe <amb@physig.ph.kcl.ac.uk>
List: port-arm32
Date: 02/03/1997 03:38:20
On Mon, 3 Feb 1997, Markus Baeurle wrote:

> > I don't know if it is possible to wire or the two interrupt lines out of
> > the 655 but if you could that would mean that you could generate both
> > interrupts on the single irq line to the IOMD.
> 
> Why shouldn't you? There must be a pin on the 665 for that and you can solder
> a wire to that.
> But can the software distinguish which port has generated the interrupt if
> they signal it to the IOMD on the same line?

RiscBSD should not have difficulty distinguishing the two serial ports.
There is a register in each serial port that will identify if the port is
generating an interrupt.
 
> There's still a problem though because you also have to build the circuitry
> between the chip and the connector. This involves soldering wires to the pins
> of the 665 which is not trivial due to its small pin spacing (probably
> 1.27 mm).

Cheers,
				Mark