[Coco] Re: Any reason to put a 6309 in a Coco2?

[Gene Heskett]

On Wednesday 31 December 2003 14:29, jdaggett at gate.net wrote:
>Gene
>
>I forgot about that. If your software is counting cycles for delays
> and stuff like that, then there will be issues. Especially if you
> are marking time from an event to trigger another.
>
>james

I suppose it could be a problem.  My problem is that I tend to think 
in terms of an os9 app, and any os9 app that times by cycle count is 
IMO hopelessly broken, it should be calling a sleep for the duration 
of the delay needed.  Of course that would depend on how much delay 
since the maximum of the minimum would be one tick, or 1/60th second.

One could also setup an SWI to handle the event, and then sleep till 
the SWI occurred.  That of course would take a hardware line.  The 
biggest problem is the relative lack of really good instructs to 
setup the SWI.  ISTR there are or was an article in the Rainbow quite 
some time ago.

For rsdos stuff, because there wasn't a clock, I'd imagine that lots 
of stuff was handled by busy waiting and counting down.  Ugly, but...
 
>On 31 Dec 2003 at 12:32, Gene Heskett wrote:
>> On Wednesday 31 December 2003 09:51, Torsten Dittel wrote:
>> >> The GIME chip is the Coco3 will not support semigraphic modes
>> >
>> >When I was talking about the "3" I referred to the "6309", not
>> > the CoCo3. Sorry for the confusion. I wondered if a 6309 running
>> > in 6809-mode would be fully compatible to an "original" 6809.
>> >
>> >Does anyone know for shure if a "6309 Level I" NitrOS9 is planned
>> > or even released? Boisy?
>> >
>> >Regards,
>> >Torsten
>>
>> AIUI, running in the default powerup 6809 mode, it perfectly
>> emulates the 6809 with the exception of doing a prefetch of the
>> next instruction if it has something else to do internally, and
>> this does increase the speed a few percentage points.  But unless
>> whatever you're doing is timed by the cpu instead of the clock,
>> you'll probably not be effected in any way you can detect.
>>
>> --
>> Cheers, Gene
>> AMD K6-III at 500mhz 320M
>> Athlon1600XP at 1400mhz  512M
>> 99.22% setiathome rank, not too shabby for a WV hillbilly
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>> by Gene Heskett are:
>> Copyright 2003 by Maurice Eugene Heskett, all rights reserved.
>>
>>
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-- 
Cheers, Gene
AMD K6-III at 500mhz 320M
Athlon1600XP at 1400mhz  512M
99.22% setiathome rank, not too shabby for a WV hillbilly
Yahoo.com attornies please note, additions to this message
by Gene Heskett are:
Copyright 2003 by Maurice Eugene Heskett, all rights reserved.