Secret agent bootleg repeating sound issue

makedome

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Hello, I'm trying to repair this jamma pcb. The game works but the sound not: there is a repeating sound that goes on and on. I checked all the audio section from z80, 2 ROMs, 1ram, 2 Yamaha ym3812 and ym2203, 2 DAC, 2 opamps, audio amplifier obviously works because I can hear sounds, 2 m5205.
Then started to check the signals starting from z80: clock and interrupts are ok but many address and data lines are high or low. Then I found that ROM ce is low and that's where I'm focusing.
If someone has some hints or could point me to a similar configuration scheme it would be highly appreciated. Thanks
 

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I presume this is a Sly Spy bootleg. The audio ROMs appear to be 2 of 27512. From their pinout, /CE being at logic low should be ok. I would look at the /OE line of the ROMs next, if that's high then I would investigate the path of signals to that pin.

p
 
I presume this is a Sly Spy bootleg. The audio ROMs appear to be 2 of 27512. From their pinout, /CE being at logic low should be ok. I would look at the /OE line of the ROMs next, if that's high then I would investigate the path of signals to that pin.

p
hello, sorry I wrote something wrong. While both rom 1 and 2 oe are toggling, rom 1 ce is low (I didn't get the active low with the # on the datasheet) but rom 2 ce is high. So I'm checking it. Despite this if I remove all that section including roms, z80 and yamahas the sound continues going on. The only way to stop it is to remove the oki m5205. I see that in the datasheet I attached reset is active high and checking it on pin 15 I see it's high. So the issue may come from that path. I already followed it back to a ls174 that proves ok so I should go back yet.
 

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I have an update: checking the ce pin on rom 2 stuck high I came to pin 2 of the gal16v8 that is next to z80. Testing it it results that pin 2 fails so I guess that's the guilty. Now the issue is that on the dump I found the gals are wrong because there are 3 16v0 and 1 16r4 which is incorrect because I have 4 16v8.
So my question is if someone has a sly spy bootleg or secret agent and dump me that gal. Or maybe you can point me to some places where I can found them. Thank
p.s.: also trying to write a new gal with some wrong code the tone which I hear changes so it seams I am on the right path
 
I have an update: checking the ce pin on rom 2 stuck high I came to pin 2 of the gal16v8 that is next to z80. Testing it it results that pin 2 fails so I guess that's the guilty. Now the issue is that on the dump I found the gals are wrong because there are 3 16v0 and 1 16r4 which is incorrect because I have 4 16v8.
So my question is if someone has a sly spy bootleg or secret agent and dump me that gal. Or maybe you can point me to some places where I can found them. Thank
p.s.: also trying to write a new gal with some wrong code the tone which I hear changes so it seams I am on the right path
I could only find 3 GALs for Master Bond (bootleg of secret agent)..


p
 
Should be 1c43 but as I try to download the set I get those.
 

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hello. I thought I found the right file for gal at ic43 but once, converted it into jed and flashed no changes. I'm sure that it's not the right rom set because I compared gal 48 with the other file and they don't match. Even flashing it and trying the video is not good.
So for now I'm pausing it. If I'll have another similar one will check.
Thanks
 
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