Hi to all,
Here is a repair log of a Namco Rolling Thunder board which had several issues ; please don't blame me if there are language errors, I'm French, I would have liked to be perfectly bilingual but I'm not.
At power up 464 is written on screen and reversed ; numbers can be white or yellow, not always the same color each time.
After searching informations about these codes I didn't find anything related, only some error codes concerning another Namco game based on a different hardware (pac land if my memory is good) so nothing really useful to help me.
I didn't notice anything on game manual too ; however number written in reverse mode is normal, no need to search for a dip switch to inhibit cocktail mode, for example.
As always I dump all the eproms to verify and compare with mame romsets (that's how I sent an unknownn Bionic commando set to Mameteam some years ago) ; nothing was wrong except one bent pin on eprom RT3-3.
This eprom is a cpu one so I hoped the board would boot but nothing more. Some chips are socketed, I tested all the rams and they were ok but finally I decided to make a more powerful test ; my eprom programmer (Dataman-40PRO) can test ics in different modes and can also make it continuous until a problem is found and that's how Ram 7N was found to be dead after five continuous readings ; I also put this ram in my chip tester pro : wrong at the first test.
I saw this ram was previously changed, a desoldered low power one wich has nothing to do here as even it is a 6264 and works, it is used to retain datas due to low consumption. Putting a new one unfortunatly only changed 464 error code in white and blue ; swapping the 2 cpus (68A09) changed nothing too. I carefully inspected solder side : no bent or shorted pins, only some minor scratches, however I decided to test scratched tracks and thanks to multimeter one was damaged, netherless invisible, near Ram located in 4N.
Now the board seemed to boot as it provided same thing than in Mame emulation but reboots infinitly when title screen appears, wathdog seemed to be activated. According to some infos on the net the culprit could be the custom CUS130. Unfortunatly I don't have another Rolling Thunder board, CUS130 have been reproduced but finally ordering one would maybe solve the problem... or not. CUS130 socket was not in good condition, replacing it with a new one didn't change anything.
I was wrong with one thing : to inspect board and change sockets easier I pulled daughter board wich is concerned by samples sounds, putting back this sub board solved boot problem ! It could be because self test search for custom chips and two are on this board.
Game starts, controls are ok but some sounds are missing, test mode reveals only PSG sounds can be listened. Music is generated by a YM2151, a DAC, and a LM324 is present. socket are in poor condition and LM324 socket had been changed by a previous owner but it was poorly done. Changing all these socket now restore music, samples circuitry have to be inspected, however. Customs chips are recognised in test mode but no samples played, touching a 47µf capacitor
of the sub board make the samples back to life, after replacing it with a new one, samples are played now. I decide to change some capacitors due to doubtful legs to prevent future issues even if they were ok.
Game was now 100% functional.
Here is a repair log of a Namco Rolling Thunder board which had several issues ; please don't blame me if there are language errors, I'm French, I would have liked to be perfectly bilingual but I'm not.
At power up 464 is written on screen and reversed ; numbers can be white or yellow, not always the same color each time.
After searching informations about these codes I didn't find anything related, only some error codes concerning another Namco game based on a different hardware (pac land if my memory is good) so nothing really useful to help me.
I didn't notice anything on game manual too ; however number written in reverse mode is normal, no need to search for a dip switch to inhibit cocktail mode, for example.
As always I dump all the eproms to verify and compare with mame romsets (that's how I sent an unknownn Bionic commando set to Mameteam some years ago) ; nothing was wrong except one bent pin on eprom RT3-3.
This eprom is a cpu one so I hoped the board would boot but nothing more. Some chips are socketed, I tested all the rams and they were ok but finally I decided to make a more powerful test ; my eprom programmer (Dataman-40PRO) can test ics in different modes and can also make it continuous until a problem is found and that's how Ram 7N was found to be dead after five continuous readings ; I also put this ram in my chip tester pro : wrong at the first test.
I saw this ram was previously changed, a desoldered low power one wich has nothing to do here as even it is a 6264 and works, it is used to retain datas due to low consumption. Putting a new one unfortunatly only changed 464 error code in white and blue ; swapping the 2 cpus (68A09) changed nothing too. I carefully inspected solder side : no bent or shorted pins, only some minor scratches, however I decided to test scratched tracks and thanks to multimeter one was damaged, netherless invisible, near Ram located in 4N.
Now the board seemed to boot as it provided same thing than in Mame emulation but reboots infinitly when title screen appears, wathdog seemed to be activated. According to some infos on the net the culprit could be the custom CUS130. Unfortunatly I don't have another Rolling Thunder board, CUS130 have been reproduced but finally ordering one would maybe solve the problem... or not. CUS130 socket was not in good condition, replacing it with a new one didn't change anything.
I was wrong with one thing : to inspect board and change sockets easier I pulled daughter board wich is concerned by samples sounds, putting back this sub board solved boot problem ! It could be because self test search for custom chips and two are on this board.
Game starts, controls are ok but some sounds are missing, test mode reveals only PSG sounds can be listened. Music is generated by a YM2151, a DAC, and a LM324 is present. socket are in poor condition and LM324 socket had been changed by a previous owner but it was poorly done. Changing all these socket now restore music, samples circuitry have to be inspected, however. Customs chips are recognised in test mode but no samples played, touching a 47µf capacitor
of the sub board make the samples back to life, after replacing it with a new one, samples are played now. I decide to change some capacitors due to doubtful legs to prevent future issues even if they were ok.
Game was now 100% functional.