Messages in this thread | | | Subject | Re: [2.1.65] New patch for serial port IRQ setup. | Date | Mon, 24 Nov 1997 13:02:42 +0100 (MET) | From | (Rogier Wolff) |
| |
Alan Cox wrote: > > > I've been made aware that some manufacturers of internal modems recommend > > using irq 2 for COM 4, while other recommende using irq 9. I've made this > > a configuration option. > > You cannot share ISA interrupts between two standard seperate ISA cards > in general. The way the cards are wired means that whoever has the strongest > drivers sets the interrupt level.
Talking about sharing ISA interrupts, has PNP changed any of this? This would've been a good time to change that situation: specify that when in level triggered interrupt mode each card provides a pull-up, and an active-low (if the lines are active-low). The pullup should be specified to be 1/5th of the minimum requires sink current, allowing upto 5 pull-up resistors in series: 5 cards can share an interrrupt.
Roger.
-- ** R.E.Wolff@BitWizard.nl ** +31-15-2137555 ** http://www.BitWizard.nl/ ** Florida -- A 39 year old construction worker woke up this morning when a 109-car freight train drove over him. According to the police the man was drunk. The man himself claims he slipped while walking the dog. 080897
| |