Seibu Kaihatsu Games

[channelmaniac]

Fixed: Raiden II:
Symptom Dead/Missing parts

Replaced missing YM3014 sound DAC IC with one from a parts board. Board would come up but caused the monitor to squeal like a pig. Had bad vertical and horizontal sync. A physical inspection showed a popped pin on one corner of the surface mount custom chip at location U0135. A closer inspection revealed many pins with broken solder connections on that IC. Resoldered the surface mount IC to fix.

[channelmaniac]

Model: Raiden II
Symptom: No sync. No boot. Board missing parts.

Board was missing 2 ROMs and one audio controller IC. Replaced the missing sound and PRG0 ROM chips with ones programmed from the MAME dumps. Fixed 3 broken traces. Board would not boot. Resoldered U0723 and U0151 to fix some graphic issues. Resoldered U0135 and U0147 and the board booted to a normal screen but would not coin up. Played in free play mode just fine. Resoldered U096, no change. Installed missing YM2151 Sound IC at U109. Board had sound in attract mode and would coin up. Tested game.

This board must have a working sound subsystem to coin up!

[channelmaniac]

Model: Dynamite Duke
Symptom: Graphic corruption

Game had every other horizontal line missing from foreground/player graphics. Surface mount chip at W3 had bent pins that were pulled off their pads. Straightened out the pins to where they wouldn't short and resoldered them in place. Tested.

These graphics are read from the ROMs in such a way that a ROM failure/issue results in vertical lines. Since the corruption was horizontal in nature, it was in the rendering section of the board.

[channelmaniac]

Model: Raiden II
Symptom: Ships and other graphics look like blocks.

Resoldered surface mount chip at U0723 and tested.

[channelmaniac]

Model: Raiden Fighters
Symptom: Dead

Cart was good, motherboard was bad. Resoldered 2 custom surface mount ICs, replaced a broken resistor pack, and tested.

[channelmaniac]

Model: Raiden Fighters 2
Symptom: Hardware Error 82

Cart was good, motherboard was bad. Resoldered several surface mount custom ICs. Board would then boot to a Checksum Error due to corrupt flash memory. Pulled the surface mount flash chip at U1053, changed the first byte to 0x10h, and rewrote the chip. Resoldered the chip onto the board and tested the game. Tested changing cartridges and rewriting the flash to ensure the memory was working properly.

[channelmaniac]

Model: Raiden DX
Symptom: Dead

Replaced a bad ROM 2. Board would then play but had missing graphics. Reflowed CPU and 2 custom surface mount chips. Tested.

[channelmaniac]

Model: Raiden DX
Symptom: Distorted, buzzing sound

Board had attempted repair damage. The YM2151 sound IC had a missing pin and a damaged socket. The M6295 IC was missing a pin, 2 solder pads, and had burn damage on it. It also had 2 jumper wires on it.

Replaced damaged YM2151 sound IC and socket. Replaced bad M6295 sound IC to fix the buzzing sound. Replaced 5 caps and 1 audio amp to finish fixing the distortion.

[channelmaniac]

Model: Viper Phase 1 - Seibu SPI motherboard
Symptom: Dead

Reflowed the CPU, Yamaha IC, Flash ROMs, and 3 custom surface mount ICs. Patched one damaged trace. Tested.

[channelmaniac]

Model: Raiden Fighters - Seibu SPI motherboard
Symptom: Checksum Error

More info: Board locked up during flash writing then would not boot past the checksum error.

Removed the Flash ROM at U1053 and reprogrammed the missing region information. Reflowed the Yamaha IC, Flash ROMs, and the custom surface mount system controller IC. Tested.

[channelmaniac]

Tip: Region information for Seibu SPI motherboards

The Region information is kept in the first byte of the Flash ROM at U1053. When changing cartridges the game will reprogram the flash information, but it will first erase the flash. This removes the region information and if the loading of the sound data into the flash chips is interrupted the region information is lost.

The region information is written to the Flash ROMs as the last step in programming them.

If the region information is lost or if the region information is incorrect (wrong region motherboard such as using a US cart on a Taiwan board) they will both show the same error on the screen: Checksum Error

To fix this, remove the surface mount Flash ROM chip and reprogram the first byte with the correct region info for the cart.

Region values that I know so far include:

    0x01 Japan
    0x10 USA
    0x20 Taiwan


If the region code for the motherboard is unknown, open the matching region cartridge, remove the PRG0 ROM and read it in a programmer. The last byte of the ROM is the region code value.

[channelmaniac]

Model: Raiden Fighters Jet 2000
Symptom: Dead

Replaced bad capacitor in reset circuit. Tested.

[channelmaniac]

Model: Raiden Fighters Jet
Symptom: No sound except coin-up

Replaced a bad CY7C421 FIFO RAM in the sound system. Tested.

[channelmaniac]

Model: Raiden II
Symptom: No sound and graphical corruption.

Cleaned board. Reset DIP switches to take game off of free play and it would not coin up. Replaced bad BG-1 ROM to fix background corruption. Replaced bad YM2151 sound chip to fix the sound issue and the coin up issue. Recapped the audio section and tested.

Note: Seibu boards rely on the sound section to make the coin up sounds before it will register the coin up. Fix the sound circuitry before troubleshooting the inputs.

[channelmaniac]

Model: Raiden Fighters Jet
Symptom: Wrong region for motherboard

Replaced PRG0 ROM with one that had the last byte changed from 01h to 10h to change the region from Japan to USA. Tested.

[channelmaniac]

Model: Raiden Fighters Jet
Symptom: Dead

When you flex the board it shows 'Checksum Error' on the screen.

Reflowed the large square surface mount Yamaha sound IC and tested the game.

[channelmaniac]

Model: Raiden
Symptom: No music, only sound effects

Board had globs of RTV holding the audio heatsink and hybrids in place.

Swapped out the hybrid and the YM3014 DAC. No change. Removed RTV and discovered the heat sink was a hacked on piece. Confirmed via Google images no heatsink was on the board originally. Removed the RTV and found a short between an audio section resistor and the heatsink. Removed the heatsink and tested music and the rest of the sounds returned. Audio amp was getting hot. Recapped the audio section and tested again successfully.

[channelmaniac]

Model: Raiden DX
Symptom: Corrupt sprites

Repaired a corroded trace going to an address line on the sprite Mask ROMs. Tested.