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Are that really screenshots, or are the pictures rendered on the fly from the savestate data? Screenshots would be a bit lame. I think using a screenshot is really the only way to get it frame accurate. If you pause the the emulation and save state, you would need to save the state from one frame a...

I got 500 internal server error twice now when posting in this thread. ISSOtm reported seeing the same thing. The post was successfully submitted though. I did try to make a test reply in the test forum and didn't get a server error then, so maybe the error is localized entirely within my thread. Si...

Test reply.

I tried changing the patches so they don't disable interrupts (writing $31 instead of $01 to $4200) and I couldn't hear or see any ill effects from it. I tried this in both Volleyball and Animaniacs with thei respective patches. I also tried running them in both PAL and NTSC, on a region modded PAL ...

The patch in Beach Volleyball is functionally the same as the SOU_TRN patch that exists in some ROMs . But instead of intercepting the command handler and checking if the command ID=SOU_TRN, it's implemented as a routine that you call with JUMP. Otherwise it does the exact same thing: disables H+V i...

I'm analyzing the Super Gameboy game Beach Volleyball because unlike most SGB games, it's using the SPC to play music. It's also interesting because it doesn't use the SGB command SOU_TRN to transfer the data. Instead it transfers code to the SNES which it calls to load the music. After the usual SG...

gekkio wrote:* Interrupts are similar to GB, but not exactly the same (NMI, amount of interrupts). Note that CGB CPUs have an NMI pin though....

Have you documented the details of this publicly anywhere?

I've solved this by having a bunch of macros that cover all relevant instructions. ;; Relocated code macros JPR: MACRO ; Relocated jump absolute jp \1+(RCODE-RCODE_S) ENDM JPRC: MACRO ; Relocated jump absolute conditional jp \1,\2+(RCODE-RCODE_S) ENDM CALLR: MACRO ; Relocated call call \1+(RCODE-RCO...

The Bung Pocket Voice apparently used the external input as well. However, this pin was also used on some flash cartridges as the /wr (write) signal for the flash chip, enabling the cartridge to be flashed with special hardware, while avoiding conflicts potential between the MBC and the flash chip. ...

It stands to reason that a game that was released as GBC exclusive is making use of the extra functionality in the GBC, and would be hard to port unless it was ridiculously unoptimized. If not, it would likely have been released as a dual platform game from the start.

Out of curiosity I tried comparing my own compression algorithm to PB16. greenhillzone.u.chrgb: Uncompressed: 1744 bytes PB16: 921 bytes Mine: 1082 bytes I think this is basically down to encoding since I use a multibyte encoding So for example, it takes a 3 byte sequence to start a backtrack operat...

How would I set that up? There appears not to be HLE for the SGB firmware , and I'm told Game Boy boot ROM is hard to dump. Thankfully, I host the various boot ROMs . Todo: Add a hash list to that page for discoverability for people who may be looking for those files. Add the GBC boot ROM. Edit: Ad...

The official Super NES port of the 240p Test Suite was 512K last I checked, and the Super Game Boy allowed downloading only up to 64K last I checked. Is there source code for a Super NES program sending requests back to the Game Boy CPU so that it can request 4K of data at a time through the DATA_T...

But not everybody can run 240p Test Suite. A. Someone owns a Super NES console, Super Game Boy accessory, and EverDrive GB, but no Super EverDrive or SNES PowerPak. It is not strictly true. The SGB contains facilities for downloading code into SNES RAM and running it. This should be enough to run a...

Good idea. That might tip the balance up to integer counts for the OAM and VRAM cases, so 2 tiles or 3 entries. Although I'd have to confirm this on hardware to be sure. If nothing else, it would make the routine more likely to work despite the presence of sprites. The extra write is 24 clocks long ...