Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site hcrvax.UUCP
Path: utzoo!hcrvax!hugh
From: hugh@hcrvax.UUCP (Hugh Redelmeier)
Newsgroups: net.micro.cpm
Subject: Re: Need Kaypro technical help
Message-ID: <1512@hcrvax.UUCP>
Date: Fri, 16-Nov-84 10:49:18 EST
Article-I.D.: hcrvax.1512
Posted: Fri Nov 16 10:49:18 1984
Date-Received: Sat, 17-Nov-84 01:38:49 EST
References: <2566@dartvax.UUCP>
Distribution: net
Organization: Human Computing Resources, Toronto
Lines: 14

I have done serial I/O on the Kaypro II (pre-1984 version) using
interrupts.
- Only the first 16K of address space is bank switched.
- Remember to put your interrupt routine and the vector above 16k.
- You must use the interrupt mode that allows you to
  specify that the interrupt vector is above 16k.
- If you are using PluPerfect CPM2.2E, it is already using
  interrupts with the SIO (using the SIO channel to the keyboard
  as a timer to turn off the disk after a few seconds of inactivity!).
  It would be tricky to share the SIO interrupts with CP/M 2.2E.
- Be careful to use very little stack in your interrupt routine:
  the interrupted routine may not have left you much.  Best to
  switch to a private stack immediately on entry to your
  interrupt routine.