C64 WarpSpeed cartridge doesn't work in MiSTer

Skyfox
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C64 WarpSpeed cartridge doesn't work in MiSTer

Unread post by Skyfox »

Has anyone been able to get the C64 WarpSpeed cartridge running on MiSTer? It was a Fastload type cartridge, but with better performance and fully featured ML monitor. The .CRT file I've been using for years on emulators doesn't seem to do anything on MiSTer. When loaded, it just displays the standard C64 boot screen. Here is more info about the cart:

http://blog.worldofjani.com/?p=5043

And, a project to open source and duplicate it:
https://github.com/SukkoPera/OpenC64WarpSpeed/

I would be eternally grateful if somebody could get this working on MiSTer. It might have something to with the address/data lines since it maps 9E00-9FFF to DE00-DFFF in a weird way that I don't understand!
Skyfox
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Re: C64 WarpSpeed cartridge doesn't work in MiSTer

Unread post by Skyfox »

It looks like both Fastload and Warpspeed work in a similar way by using $DE00-$DFFF to hold vectors and stub code which then switches in/out the rest of the rom:

https://comp.sys.cbm.narkive.com/WkbYZz ... ridge-boot

So, why does Fastload work fine in MiSTer, and not Warpspeed?

I have tried using Fastload as a substitute, but there are 2 major problems:

1. My entire disk library was written at skew-6 by Warpspeed. So, it does indeed load at warp speed with that cart, but limps along on impulse power with Fastload. I'm guessing that was probably optimized for the 1541 default skew-10.

2. The Warpspeed monitor can assemble code, Fastload's cannot.

Can anyone offer some insight into why this cart won't work in MiSTer? Does there need to be a patch or something?
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WarpSpeed_v2_1987.zip
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Epyx_FastLoad_1984_v3.zip
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Flandango
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Re: C64 WarpSpeed cartridge doesn't work in MiSTer

Unread post by Flandango »

WarpSpeed doesn't work in Mister because the cart type (#16) isn't implemented at the moment.
The cart, just like others, has additional circuitry aside of the rom, that has to be "implemented".
Skyfox
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Re: C64 WarpSpeed cartridge doesn't work in MiSTer

Unread post by Skyfox »

Here are the schematics and parts list for the Warpspeed cart (pgs. 13-14):
https://rr.pokefinder.org/rrwiki/images ... matics.pdf

Aside from the rom itself, all I see is a 74LS109 flip-flop. Is that difficult to implement?
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