From: James Carpenter (jimc@hal.gnu.ai.mit.edu)
Date: 12/15/92


From: jimc@hal.gnu.ai.mit.edu (James Carpenter)
Subject: Re: Serial IRQ polling
Date: 16 Dec 1992 03:26:54 GMT

In article <ADAMS.92Dec16013812@PDV2.pdv2.fmr.maschinenbau.th-darmstadt.de> adams@pdv2.fmr.maschinenbau.th-darmstadt.de (Adams) writes:
>There is no reasonable way to poll a device in a multi user or
>realtime environment. Attaching to a timer
>will lead to a desastrous performance loss, and hooking the
>CPU will disable multitasking.

It is interesting that Coherent could do this with no problem. There was a
small decrease in speed but who cared... it ran unbelivably slow anyway.

>If there would be enough interest, it would be neither too hard nor
>too expensive to throw an expansion card together, handling 2-4 serial
>ports without any intervention of CPU.....

That sounds rather nice.

        -Jim Carpenter
         CARPENTER@Eisner.DECUS.Org
         jimc@gnu.ai.mit.edu