So a little bit of progress in the short time I've had today.
Exxos's reply prompted me to rig an accelerator block. I've based it on reset and the first access to the bus control register of the COMBEL. When reset goes low, the clock is blocked from bursting to full speed. On first access of the bus control register, the clock is allowed to gear up. Seems to work well enough for now and I've got the 50MHz oscillator booting
Not too terrible on the GB6 scores:
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Some tasty AltRAM speeds on NemBench:
- IMG_4759.jpeg (175.83 KiB) Viewed 2028 times
23.6 on
@czietz's Coremark is the best I've achieved yet.
- IMG_4758.jpeg (166.64 KiB) Viewed 2028 times
And a solid 3600 frames on the Frontier Intro benchmark.
- IMG_4761.jpeg (114.03 KiB) Viewed 2028 times
That said, this is my old and very inefficient (in terms of CPLD space) SDRAM controller and there's the occasional problem still. Frontier hung a couple of times. Doom under MiNT has been hit and miss, so that's still a target for attention.
Whether that comes first or the FPU will depend how deep I feel like going next time out, I think.
But a decent night's work, I reckon -- providing I've not toasted my FPU
Cheers,
BW
DFB1 Open source 50MHz 030 and TT-RAM accelerator for the Falcon
DSTB1 Open source 16Mhz 68k and AltRAM accelerator for the ST
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark