[Coco] 6309 running in a Coco 1

[Luis Antoniosi (CoCoDemus)]

I tried building a coco1 6309 now and after fixing few syntax errors
(maybe mamou wasn't so assertive) the system will hang on boot. I
tried on mess coco3h. Can't test on real hardware as I'm bed ridden
for a while. As Xmas gift I broke my ankle...i might be naughty :(

On Fri, Jan 3, 2014 at 12:17 AM, William Astle <lost at l-w.ca> wrote:
> This is actually incorrect. 6309 native mode has nothing to do with clock
> speed. All it does is change the cycle counts for many instructions. It does
> not change the clock speed. In fact, the CPU itself has exactly zero control
> of the clock speed and the switch to native mode is a flag in a CPU
> register. You can perfectly happily run a coco 1 or 2 in 6309 native mode.
>
> On 14-01-02 09:35 PM, Bill Pierce wrote:
>>
>> The problems I see with this is that you couldn't run in 6309 native mode
>> on Coco 1&2. (Dragons too I think). Since the 6309 native mode runs at
>> double clock speed, the Coco 1&2 would lose video just as it does when using
>> the poke65495,0 & poke65497,0 in Basic. It's the very reason the double
>> clock wasn't used by software on the 6809 back in the 80s. The VDG chip can
>> not take the speedup. Possibly the SAM as well (???). On the Coco 1, the
>> bitbanger port cannot use this mode as well. That's why there's no "Turbo
>> mode" DW4 drivers for Coco 1. The Coco 1 had a flawed serial output and
>> maxes at 38,400.
>
>
>
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