[Coco] CP/M emulator for OS9/6809

Retro Canada retrocanada76 at gmail.com
Sun Apr 27 17:49:39 EDT 2014

the 6309 is put in native mode during boot and never changes back to 6809.

IRQ/FIRQ are not compatible between modes as you have more registers pushed in native mode.

and each application has a 64k window you cannot extend that without cheating.

On Apr 27, 2014, at 5:26 PM, Nick Marentes <nickma2 at optusnet.com.au> wrote:

> On 28/04/2014 7:13 AM, Retro Canada wrote:
> if you run os-9 level 2 in 6309 it's already in native mode which is 30% faster on average. this is what i do at home. there are some instructions that i could benefit from 6309 but dont think it would make any major impact. i made it for 6809 to not restrict the audience.
> what could really speed up would be using lookup tables for some instructions byt this would take more memory than the coco itself could handle.

But because the OS is 6309, does that translate to all programs?

I know you can turn on 6309 and get faster execution of all codes but the speed boost is obtained from writing 6309 native and utilizing some of the extra commands.

This is my understanding and what I was referring to for Luis's CPM emulator.

As it stands, it's not really practical to use any CPM programs because of the speed. Shame because Luis has done a great job of making it run at all. Just needs that little bit of extra speed to put the icing on the cake.

Also, doesn't Level 2 OS-9 utilize more memory or are applications still restricted to a 64K memory space?

Sorry for my lack of knowledge in OS-9, hence the many stupid questions.   :)


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