More PC-FX

I now have the demo booting on a real PC-FX. I also applied the patch directly to the _startup.o file. Getting the game to work on the real hardware is probably the biggest challenge in developing for a system.

The next big hump is the Magic Engine FX emulator. The Magic Engine FX tech demo locks up in the VSyncWait routine.

I have to learn alot of information about the PC-FX before moving forward.

NEC PC-FX could be next!

I am working on adapting the PC-FXGA development kit to develop games for the NEC PC-FX.

Here's a screenshot of a demo program included with the development kit:

Currently the input is not working, and the code to initialize the input causes the program to crash.

Frog Feast Neo Geo version released with Source.

I've released the complete Neo Geo version, including source code.

I added the title music and background sound to the PCM roms. I had to switch to the mutation Nation game, which has 2-1MB sound roms (v1 and v2).

The game number has been changed to 273, which is the next NGH number after the last released Neo Geo game.

CPS-1 Frog Feast has sound.

I've added sound to the CPS-1 version of Frog Feast. It does not have the music, since it is too big to fit in the sound roms.

This was very easy to implement. The sound table is located at the front of the sound roms, and not in the Z80 roms.

The sound format is 4 Bit Dialogic ADPCM at 8000 hz 16 bit mono. This is almost the same as the X68000. The CPS-1 uses an earlier version of the OKI chip used in the X68000.

The source code and build instructions have been released.

CPS-1 version nearly complete

I've almost completed the CPS-1 version of Frog Feast. The game is fully playable, only missing sound and music.

The sprites and text were very easy to implement. Sprites are always treated as 16x16 pieces, regardless of size. The splash is a 32x32 sprite, it gets broken down into 4 16x16 pieces. The sprite system allows for linking of the pieces.

The last remaining feasture is sound and music.

CPS-1 Version Started

I've started the CPS-1 version of Frog Feast.

The biggest problem with this version is my poorly documented code from the initial CPS-1 arcade demo. Another problem that I ran into was my tools for writing CPS-1 tiles. I should've been reading in all 4 graphics roms, but I was only reading in two. This mysteriously causes some of the graphics bitplanes to disappear, except for the last set of tiles added to the roms.

The CPS hardware is a bit different than normal, since it uses color 15 as transparent (instead of color 0).

The 8x8 tiles are also a bit weird, since they use 16x16 tiles to represent 8x8 tiles. The left and lower parts of the tile are unused in 8x8 tiles.

Each scroll only seems to be 256 pixels high (16 tiles in 16x16 and 8 tiles in 32x32). But, the scroll is documented as being 64x64, the rest of the map may be located at another place in the scroll.

I'm not sure why they limited parts of the palette to sprites and scroll. Each scroll and the sprites have their own 32 palette block (16 colors per block). It would be nicer if the palettes were available to all scrolls, but 32 palettes isn't a big limit.

The next thing I plan to work on is the text layer, and adding sprites.

X68000 Fixed, again.

When a program is started from AUTOEXEC.BAT, it starts at $35630 (header at $355F0), instead of $355F0 (header at $355B0). The extra information appears to be exe data or something. Anyway, this was a quick fix...

X68000 Resolution Fixed

I fixed the resolution in the X68000 version of Frog Feast. I changed it to 320x224, based on the settings used in Puyo Puyo. The emulator draws the screen as 320x448, but that's based on the height being interlaced.

This version is now wrapped up.

X68000 Frog Feast near complete.

The X68000 version is pretty much complete.

The X68000 version was pretty easy to wrap up. I got the sound effects in. They are stored in 4 Bit Dialogic ADPCM format at 15,625 hz 16 bit mono. The sprites were very easy also.

The only problem I am currently having is getting the screen set correctly. The current screen resolution runs slowly. Changing the screen resolution fixes the problem. It's a problem with the triggering of the VBlank interrupt. I need to research this a bit more. The only other thing to consider is getting the title music track into the game. I'm not sure if there is room in RAM though. I have to wait for my X68000 to arrive to test this out on real hardware.

I am looking into publishing this game.

X68000 Frog Feast text layer working.

I got the text layer working on the X68000 version of Frog Feast. It was a fairly painless addition.

I was expecting the text layer to be tile based, similar to the Genesis or something. Instead it is 4 seperate bitplanes. The bitplanes can be written to as a seperate bitplane or as 2 to 4 combined bitplanes. The palette is taken from palette #15 (zero based index).

The next planned additions are joystick reading and sprites.

Frog Feast for the IGS PGM finished.

I finished the IGS PGM version of Frog Feast. This includes sound and music playback. I had to omit the background sound due to space limitations of the sound rom, all other features are included though. I also released the source code and tools necessary to build the roms.

I will now be able to work on the X68000 version of Frog Feast.

Frog Feast for the IGS PGM finished.

I finished the IGS PGM version of Frog Feast. This includes sound and music playback. I had to omit the background sound due to space limitations of the sound rom, all other features are included though. I also released the source code and tools necessary to build the roms.

I will now be able to work on the X68000 version of Frog Feast.