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There was a retrogaming meeting today over here. I used the Dragon 64 for the first time. Awesome!

jmk wrote:A nice bundle! The things that caught my eye were the C128, Oric Atmos and the Tatung Einstein 256 - quite a rarity. I'd love to get a CoCo 3 myself!

Thank you very much!

I use that CoCo 3 with a Super IDE cartridge, it is really awesome.

jmk wrote:I'd love to get a CoCo 3 myself!

Same here! I have been looking to buy the PAL version of the CoCo 3 for years, but they just don't ever seem come up for sale anywhere.

Garrettimus wrote: I use that CoCo 3 with a Super IDE cartridge, it is really awesome.

Marcus, you should quite easily be able to use your Dragon 64 with the SuperIDE cartridge.
See my post here: viewtopic.php?f=5&t=779

The VCC emulator runs the emulated CoCo 3 at double speed if you enter POKE65495,0 at the command prompt of the emulated machine. I have always wondered if this was simply a feature of the VCC emulator, or if a real CoCo 3 would behave the same way. Does your real CoCo 3 run at double speed if you enter POKE65495,0 at the command prompt?

Hmm, the CoCo3 is certainly capable of running at double rate constantly (the GIME is clocked twice as fast as the SAM, and interleaves data at double the rate).

But the poke you're talking about is the address-dependent rate one (in SAM-speak). I'm pretty sure the GIME doesn't do AD, but whether it will interpret that as double speed or not I can't say... If nobody else gets back to you, I'll try it out later!

sixxie wrote:If nobody else gets back to you, I'll try it out later!

I would be grateful if you would try that little test.

The address-dependent rate poke appears to have no effect.

I tested with a simple TIMER-based print loop, both in the default RAM configuration (POKE &HFFDF,0) and ROM (POKE &HFFDE,0) - though my only verification that I'd switched to ROM was that the CMP and RGB commands ceased working.

POKE 65497,0 does enable double speed mode, of course (RAM and ROM config).

Thanks Ciaran! I appreciate you taking the time to try this test. As I suspected, both MESS and VCC suffer from this serious flaw in their emulation of the CoCo 3 hardware.

No problem - it's useful to know!