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Recording the music from Gryzor is a real pain. The test mode only plays a few seconds of each sound, and if you halt the main CPU for more than about 5 seconds, a watchdog kicks in and resets the whole board. So you need to defeat the watchdog by powering the board up, then (once the POST is complete) tying _RESET of the game CPU high. You can then start the sound you want to record and halt the game CPU. The sound CPU will then run unmolested; the watchdog won't be able to reset it. Be grateful I went to all this trouble 8-)

realaudio music:

BGM $38 (352K).
BGM $3B (176K).
BGM $3C (264K).
BGM $3D (242K).
BGM $3E (242K).
BGM $40 (286K).
BGM $41 (242K).

Gryzor (Contra)

Gryzor title screen
Good ol' Lance and Bill..

Gryzor (sold as Contra in the USA) is one of Konami's success stories, mega-epics that spawned several sequels and conversions to every home computer and console platform known to man. In this respect (and in its gameplay), Gryzor is similar to the legendary Castlevania series. There are at least five completely separate games in the Contra series; Gryzor/Contra, Super Contra (SNES only), Contra 2, Contra 3, and Contra 4. Contra 4 was converted very competently for the Sega Genesis/Megadrive, and it could best be described as a long series of bosses with occasional bits of levels in between; an extremely difficult game.

However, back to the 1987 original you see illustrated. Good ol' Bill and Lance. As you can see, these gun-toting commando types walk through a series of side-scrolling (and sometimes vertically scrolling) levels. At the end of each level, there is a primitive 3D into-the-screen section just before the level boss. There is really quite a bit of variety in this game!

The game runs on two 68B09EP CPUs, and it's very neatly laid out; it looks easy to emulate. Sound is provided by a YM2151 FM synthesizer and a YM3012 DAC.There are two layers of 8x8 tiles, independently scrollable, and a reasonably large number of sprites, approx. 16x32 pixels or so. At the time of writing, work on an emulator (DOS-based) for this board is almost complete (only sound is missing, and a few colors are incorrect); if you are reading this after about March 1998, you should be able to locate the emulator by running a web search. Please note that my only involvement in this emulator was providing technical advice to the author; I cannot answer questions, deal with emulator bugs, or provide ROM images.

If you get the chance to buy this board, do so. It's definitely high-tech (for 1987 technology), with parallax scrolling backgrounds and nice colorful graphics, not to mention quite enjoyable music and good, if difficult gameplay.

Gryzor uses a vertical low-res monitor, two 8-way joysticks with two buttons, and it has a standard JAMMA pinout. NB: The clone board's notes say that it is designed for a supply between 4.85V and 5.25V. DIP switch settings are as below:

DIP Switch Bank 1

* indicates a factory default setting.

1 2 3 4 5 6 7 8
Coin 1 1 coin 1 play 0 0 0 0
1 coin 2 plays 1 0 0 0
1 coin 3 plays 0 1 0 0
1 coin 4 plays 1 1 0 0
1 coin 5 plays 0 0 1 0
1 coin 6 plays 1 0 1 0
1 coin 7 plays 0 1 1 0
2 coins 1 play* 1 1 1 0
2 coins 3 plays 0 0 0 1
2 coins 5 plays 1 0 0 1
3 coins 1 play 0 1 0 1
3 coins 2 plays 1 1 0 1
3 coins 4 plays 0 0 1 1
4 coins 1 play 1 0 1 1
4 coins 3 plays 0 1 1 1
Free play 1 1 1 1
Coin 2 1 coin 1 play 0 0 0 0
1 coin 2 plays 1 0 0 0
1 coin 3 plays* 0 1 0 0
1 coin 4 plays 1 1 0 0
1 coin 5 plays 0 0 1 0
1 coin 6 plays 1 0 1 0
1 coin 7 plays 0 1 1 0
2 coins 1 play 1 1 1 0
2 coins 3 plays 0 0 0 1
2 coins 5 plays 1 0 0 1
3 coins 1 play 0 1 0 1
3 coins 2 plays 1 1 0 1
3 coins 4 plays 0 0 1 1
4 coins 1 play 1 0 1 1
4 coins 3 plays 0 1 1 1
Invalid 1 1 1 1

DIP Switch Bank 2

* indicates a factory default setting.

1 2 3 4 5 6 7 8
Lives 2 0 0
3* 1 0
5 0 1
7 1 1
Cabinet Type Cocktail 0
Upright* 1
Bonus Life 30000/70000* 0 0
40000/80000 1 0
40000 0 1
50000 1 1
Difficulty Easy* 0 0
Normal 1 0
Hard 0 1
Hardest 1 1
Attract mode sound No 0
Yes* 1

DIP Switch Bank 3

* indicates a factory default setting.

1 2 3 4
Screen Invert Normal* 0
Reverse 1
Controls on upright cabinet Single* 0
Dual 1
Test Mode Play* 0
Test 1
Sound Stereo* 0
Mono 1


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