The FPGA Videogame Console


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Creatom. Gawd, what a fucking piece of shit! The game is OK (and very very very odd) but the mapper is insane. There's some nasty, nasty shit going on. The game periodically checks the mapper for stuff, and if it's not right, the game crashes. I had to add some special "readback" circuitry for this POS to run. But it runs now.




"Creatom: A world inside your mind."




Mapper 33 sucks too. It's really 2 or 3 different mappers in one. I had to write some special code in the BIOS to figure out which game was being run, so I could select the proper sub-mapper. GRRRRR. Stupid japanese mappers!




The amusing blurring is caused by my ultra-slow digicam.




Super Donkey Kong, w00t. The green line is the green emphasis bit being controlled by ShoRQ(tm). ShoRQ(tm) turns the green on for 256 CPU cycles when the IRQ line goes high (after it was low, triggering an IRQ). This graphically illustrates where IRQs hit for easier debuggage.




This amusing screen pops up for literally around 5 frames on startup; it's so fast that you cannot read it. It took around 6 tries for me to catch it.




The kept the IRQ counter set to where it was, but just don't use the resulting IRQ.




Yeay! I got Help Me Nicol running! This is another FDS conversion. The FDS audio is perfectly intact like on the other FDS pirate (Bio Miracle). This is a really spiff-o game. I know that both games were made by the same pirate, because the BIOS area contains the same code.




Another screenshot of the above game.




Yeay. Another "pirate original". For some reason, this game works perfect up until when it's supposed to start. Then it just wedges. Game doesn't seem to crash or anything, but it just stops.




Showing off ShoRQ(tm). This shows where SMB3 uses it to make up the bonus game.




I was playing around with mapper #65.. yet another 2 or 3 or more mappers in one (grrrr) trying to get it going, and I had PRG banking wrong. This screen came up when the game crashed!! I found it kinda amusing.




This also came up when the game crashed.




Take a last look, 'cause this is the last time the old sprite render engine will be working. It took me around a week to get the new, proper, sprite enging working.




After re-designing the sprite engine to conform with the experimental data Quietust and I gathered using his sprite fetch proggy, this is the first go. It doesn't look very good does it.




I was using all 3 emphasis bits to display various things, like the state machine state bits and other crap. needless to say, it's all fuckered up.




Nope, I didn't fix it yet.




Now we're getting somewhere. I at least have something resembling sprites again, but it's still just not right. I wouldn't learn until later that all my problems were the result of a VERY STUPID fuckup on the sprite priority encoder. All the select lines were flipped around. Grrrr.




After dorking around, I got it working to this point, but all the sprites were shifted over 1 position. Sprite 0 was showing up as sprite 7, sprite 1 was showing up as sprite 0, etc. A dumb error was the source of the trouble, and a quick fix later I had it working fine.




Yeay. Everything's working right again. The highlighted blue 00 indicates sprite 0 was found. I extensively tested everything out with this program and it all works great.



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