Graftgold games

[redmoonlevel9]

I seem to recall there being a particular reason why certain WHDLoad games don't work on the minimig when in A1200 config, mostly from Graftgold but there are others too.
I'm currently using a hardfile image from my Amiga 1200 which works fine on the real machine, but games like Uridium 2 and Rainbow Islands don't work on the minimig.
Any idea if this will ever be fixed or is it just something intrinsic that cannot be remedied?

Cheers.

[Neo666]

There are a handful of games that don't work due to some unimplemented 68020 instructions, the floppy version of these games work just fine in OCS though

[redmoonlevel9]

Yeah I realise the floppy versions work fine it would just be nice to have everything working from the HD, I have it set up with iGames and images for each game etc.
I didn't think it was a matter of unimplemented instructions though, rather something not easily resolved.

[Lisko]

Yes 68000 is cycle accurate while 020 unfortunately not

[CapnChaosDK]

Yes 68000 is cycle accurate while 020 unfortunately not

020 comes with all kind of different frequencies on the Amiga, so nothing to be cycle accurate against. If you wanted it to be cycle accurate, then a target is needed, like stock A1200 or another accerator.
It is the instructions that are missing and/or incorrect.

[Chris23235]

For the Uridium HDF, you can switch to the 68000, while maintaining the AGA chipset.

[Optiroc]

All the non-working Graftgold WHDL slaves throw the number 10 “unimplemented instruction” exception. Is it likely that that’s the root cause, with both the game and slave being 100% 68000 code? Another possibility is that the CPU jumps to a bad address due to some other error.

[redmoonlevel9]

Interesting stuff.
My real Amiga 1200 has an 030 based accelerator in it with 8 megs of fast ram.
With Uridium on the minimig it always fails as it's about to do the copper bars effect.

I'll try running it as a stock A1200 with no accelerator and see what that does.
Shame I'm not an FPGA programmer, would be nice to know what's actually going on with it.
I imagine it's nothing that's easily fixed.

Btw I'm happy we have a mister forum now, feels right and proper!