Subject: Re: Fix for your serial/PPP problems

From: [email-masked] (renald loignon)
Date: Thu, 22 Aug 1996 00:18:53 -0400 (EDT)

>renald loignon ([email-masked]) wrote:
>: Could someone knowledgeable in low-level kernel matters take a look at the
>: following?  I looked at the Web page, and though it sounds interesting
>: overall (and it WOULD solve a serial problem I experienced with Debian 1.1.1
>: and kernel 2.0.6), there appear to be some technical inaccuracies which give
>: me second thoughts. Any comments appreciated.

>What are the inaccuracies you are referring to? Seems to be ok 
>as far as I can tell except I dont know enough about PIC 
>programming to tell if he is right on that.

Well, one example from his Web page:

"irqtune defaults for a standard IRQ configuration. It assumes that 
 the highest priority device should be on IRQ 3. This is normally the 
 first serial port on standard configurations, which is what you want. "

Unless something has changed since I wrote my first interrupt-driven serial
driver on an XT, under PC-DOS 2.0, COM1 uses IRQ4, whereas COM2 uses IRQ3.

 On the other hand, if you have a serial mouse on COM1, it is likely that
the modem will be on COM2, and therefore his default action of giving
maximum priority to IRQ3 actually makes sense, despite the incorrect
statement about the _FIRST_ serial port being on IRQ3.

I thought there was something else wrong in his explanation of interrupt
numbers and priority numbers, but after a second reading, it seems I was
mistaken.