Thursday, 24 July 2014


Haven't had much time over the last week or so; the whole family has been sick at various times and I've been trying to fit more physical exercise in which is not conducive to other non-essential activities.

Whilst sick, and not feeling up to a full assault on the Lode Runner code, I started looking at the so-called eye-catcher routine in the BIOS. This is the routine that displays the spinning NEO GEO logo and the other bits of text on the screen at power-up (or reset) before the cartridge takes full control of the system.

The routine itself can be enabled, disabled or overridden by the cartridge with a single byte in the header. Even when enabled, the BIOS routine uses tiles and sprites defined by (stored on) the cartridge itself. Since I'm not interested enough to code my own eye-catcher routine, I thought I'd see how difficult - or otherwise - it would be to produce my own custom text for the BIOS routine.

The results of my investigations have been documented on the Neo Geo Development Wiki here.

My first experiment was to replace the "MAX 330 MEGA" text. It looks pretty good, but needed something on the following line (to replace "PRO-GEAR SPEC"). There was an issue with that (see the wiki entry) but I might return to this option.

My next experiment was to replace the SNK logo. Not quite sure whether or not I like it yet!?!

Anyway, at the very least, I learnt something new.

I've also had a think about what I'll be releasing and when. I was toying with the idea of the initial release of the Coco 3 port being cartridge-only, but I've now decided that it would significantly delay the release and also further delay what should be my primary focus - NGPACE.

As a result, I'm going to finish off the C port as a matter of urgency and release the Neo Geo MVS and CD versions, then immediately move on to finishing a disk-based Coco 3 port and release that in the near future. I'll still work on the Amiga and Genesis ports, but I don't want them to delay the above-mentioned releases.

I also plan on ultimately releasing the original 6502 disassembly and the C source code, probably once the Amiga & Genesis are done. Then it's time to move on to another game.

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