RoboCop 1 arcade demo intro music missing

thearcadeguy

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I just recently obtained a Robocop 1 arcade game and all the RoboCop's that I have come across when you turn it on have the theme demo music as the RoboCop logo is flashing mine has no theme music but I do have the intro sounds where he says RoboCop serve the public trust protect the innocent uphold the law but not the demo music in the intro I was checking into the dip switches in the demo Music and Sound is on from what I'm looking at could there be a corrupt eeprom or is there a eprom just for the music part it's a data east board any help would be great also I am a video game technician but I have never come across a Robocop
 
OK.I think the problem lies in the circuit that generate the music (6502+YM3812+YM2203).
All the sound effects (speeches, etc.) are played, instead, by the OKI MSM6295 (which is located on ROM board).
 
The 6502 still drives the OKI, so if that's working it's likely the actual sound program eprom is ok. The YM DACs or amplifiers are most likely cause (as caius says :) ). If I remember right music is purely the YM3812 - and sound effects the YM2203.
 
The 6502 still drives the OKI, so if that's working it's likely the actual sound program eprom is ok. The YM DACs or amplifiers are most likely cause (as caius says :) ). If I remember right music is purely the YM3812 - and sound effects the YM2203.

If I remember correctly the OKI MSM6295 is ruled by the "DATA EAST 45" custom which is nothing more than a Hu6280 in disguise :)
Both are on ROM board.Anyway, try to load in MAME a dummy 6502 code ROM and see what happens :)
 
On Robocop and Hippodrome the Oki is 100% guaranteed driven from the 6502 - the 45 is used as protection only (it maps into main cpu address space).

45 wasn't used as the sound cpu until Sly Spy, Midnight Resistance, Vapor Trail, etc.

:)
 
On Robocop and Hippodrome the Oki is 100% guaranteed driven from the 6502 - the 45 is used as protection only (it maps into main cpu address space).

45 wasn't used as the sound cpu until Sly Spy, Midnight Resistance, Vapor Trail, etc.

:)

I looked at schematics and this is correct so the CPU 6502 is doing his job since some sound FXs are correctly played.
Can I see some repair logs from you? :)
 
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