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[epaell]

When I shifted to the W6 setting I had the same garbled screen regardless of whether I had the 12 MHz or 16 MHz clock. With the W4 setting things worked fine with the 12 MHz clock but would sometimes seemed to ignore commands sent to the VDP (but the screen would not be garbled).

In other news, I was able to get OS9 running in 6309 mode. This now works on both the DIP 6309 and the PLD one - so both are actually working fine now. The fix was basically to do the same as what the coco version was doing i.e. I just created another copy of the directory and referred back to the 6809 version for the makefiles (with the addition of the 6309 definition). I'm not sure how this is different to what I had originally - perhaps I missed a definition somewhere.

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September 17, 2024  13:12:25
NitrOS-9/6309 Level 1 V3.3.0 on the MECB 6809  2024/09/17 13:12:26


User name?: user1

Process #05 logged on   2024/09/17 13:12:28
Welcome!

Welcome to NitrOS-9 Level 1!


Shell

OS9:cputype
CPU: 6309, running in 6309 native mode.

[Editor]

When I shifted to the W6 setting I had the same garbled screen regardless of whether I had the 12 MHz or 16 MHz clock. With the W4 setting things worked fine with the 12 MHz clock but would sometimes seemed to ignore commands sent to the VDP (but the screen would not be garbled).

Did you mean that W4 was garbled regardless of 12MHz or 16MHz, but at W6 it was fine at 12MHz?

W6 is the longer delay. So, if you did mean W6 was garbled at both 12 & 16MHz, but W4 was okay at 12MHz, then something else weird is going on! (You definately cut the W6 track?)

Either way, it would be interesting to see if a 74AHCT244 makes a difference. If you get the opportunity to try one.

In other news, I was able to get OS9 running in 6309 mode. This now works on both the DIP 6309 and the PLD one - so both are actually working fine now.

That's great (and also relieving), news!

[epaell]

Did you mean that W4 was garbled regardless of 12MHz or 16MHz, but at W6 it was fine at 12MHz?

My apologies, yes that is what I meant to write (I was jumping around between working on the 6309/6809 issue and this other issue and was getting a bit careless with my typing).

I don't have any AHCT devices on me at the moment but next time I place an order I'll include some of those as well to give this a try. It's not a major blocker and everything else seems to work fine at full speed. I just ran some speed tests and get 4.8s for 10 iterations of sieve at 16 MHz with the 6309 setting (6.4s at 12 MHz and 5.1s at 16 MHz with the 6809 setting). It seems to be marginally faster with the 6309 compared to the 6809 (for timing I ran 100 iterations just to get better timing accuracy). I guess this makes sense since in native mode some of the instructions can be a cycle or so faster compared to the 6809, neither the compiler nor the OS are really optimised for the 6309 so I guess it isn't using it to its full capacity. Either way it is giving other computers of the time a run for their money: