Some questions about Starfox 2 repro's

[Sonny_Jim]

/flamesuit donned
Hi all, I'm thinking about doing a small run of Starfox 2 reproductions and I've got a couple of questions about it:

Q1. Can anyone confirm that the translated version of SF2 does not work when used with a Winter Gold donor? (Yes, I know that you can just use Stunt Race FX, it's just that I have a WG lying around). The closest I got to an explanation was a post on Cherryroms:

Fire1701 wrote:

D4s told me, that you can not use Winter Gold FX for a translated Version of Starfox 2. The Game will hang on the Titlescreen since the logo was changed. Nobody knows exactly why the GSU 2 has problems with the trans. Version. maybe there is a problem with the compression format of the new logo. The GSU 1 works perfect with a trans. Version.

This is most likely a problem in the translation. There may be hardware restrictions when running at the higher clock speed that we don't know about which were handled by the original developers but not by the translator (because we don't know what the restrictions are). We've seen many a non-special chip translation that violated hardware restrictions such that it breaks on a SNES and this has additional complexity.

EDIT: And just to confuse things further, there's this post here:
http://www.assemblergames.com/forums...l=1#post220789

Q2. I'd like to minimise the amount of soldering I have to do and saw this code that reaaranges the ROM file so the pins are closer to the maskrom:
http://www.assemblergames.com/forums...l=1#post220884

Can anyone confirm that this works OK? Thinking about it I'm going to have to use 32 wires due to the EPROM being bigger than the maskrom, swapping around a few lines isn't going to save me that much trouble. I suppose if I was using SMT chips it would be easier but I'm looking to use just plain old M27C801's.

Q3. When using Stunt Race FX donors, I've read that some early carts were unsuitable as donors due to the clockspeed being halved. Is this just nonsense or do only specific revisions of Stunt Race FX work?

Apologies if this is in the wrong forum and I understand that Starfox2 can be a very contentious issue on these forums.

[Bad_Ad84]

Q1 - I have used GSU-2 carts with no problem.

Q2- I wouldnt bother, just wire it "normally" its about 5 pins that are swapped.

Q3 - Nonsense and misinformation. In the thread you linked it has the correct info:

http://www.assemblergames.com/forums...l=1#post222187

[Sonny_Jim]

Thanks Bad_Ad84,

Regarding Q1, I've not seen a definitive answer to this question yet, the closest I've seen is that post I linked to which uses the translated-but-still-debug version. The thing that worries me is that it was d4s who said that it didn't work and he seemed to know quite a bit about the SFX chip. I suppose I'll find out for myself when I have a go at it.

[Bad_Ad84]

I used the patched rom (title screen + removing debug output) on a doom cart (which is GSU-2) and it worked fine.

[Sonny_Jim]

I can't think of any reason why a WG wouldn't work when a Doom works just fine, presumably the PCB's are identical apart from Doom missing the circuitry for the SRAM battery.

From what I've read, GSU-1 carts should work fine (Stunt Race FX) as they are capable of running at 21MHz and it's selectable by software. I did read somewhere that a hardware mod was needed for *some* Stunt Race FX carts as they started up in 10MHz, but I'm pretty sure that's a load of nonsense.

The one thing I do know is that there is a *lot* of misinformation about the differences between the 3 chips and overclocking them. I'd love to dispel a few of this myths.

[Bad_Ad84]

I added the battery backup circuit to the Doom cart and that still worked fine too.

[MottZilla]

Even if a Stunt Race FX cartridge starts in low speed speed, the game software sets the speed register (just like Star Fox 2 will) and this is not an issue. Some complaints about speed particularly related to Star Fox 2 may be because people believe the framerate should be smoother or better due to their experience on ZSNES or other emulators which do not emulate the timing and cache delays of the real Super FX chip and thus perform somewhat better.

Star Fox 2 should run just fine on any Super FX with enough RAM, except for the original Star Fox cart that uses the Mario Chip version of the Super FX that cannot run in high speed mode. GSU-2 is not needed because the game is only 8 megs. GSU-2's main difference from GSU-1 is an extra address line for the MaskROM. Yoshi's Island and Doom require GSU-2 because they are 16 meg MaskROMs.