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Tech and Marketplace => I need help with my game! - Technical Discussion => Topic started by: Tate10 on April 01, 2014, 12:39:22 pm



Title: Galaga rebooting over and over? Video attached.
Post by: Tate10 on April 01, 2014, 12:39:22 pm
Wondering if anyone has any advice on where to start.  The game just keeps cycling the start sequence over and over.  Thanks Tate

http://youtu.be/qNLU3gICLnU


Title: Re: Galaga rebooting over and over? Video attached.
Post by: iankellogg on April 01, 2014, 01:05:24 pm
It looks like it is having some ram issues. I could be wrong but the fact that the test pattern is messed up is a sign of something wrong with the PCB most likely in the RAM->video stuff.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: lesoleil70 on April 01, 2014, 01:27:24 pm
check the roms maybe , just like the pacman video john did.  Might have been the gyruss.
the one where he compared the files to a trusted rom download source.


pulled this from arcadeotaku

Symptom: Reboots constantly
This is different than the bad CPU socket problem in that it wasn't stuck at RAM OK but rather as soon as the crosshatch then the text came on the screen it rebooted. The Reset line on CPU #2 and 3 came active for a VERY short period of time then the game reset.
Swapped out the CPU sockets. Subbed out the custom chips. Nothing. On a whim I turned off each DIP switch and found by playing with them that when DIP switch #3 at 6J was on it would cause the system to lock up when running or to constantly reset when booting.
Replaced the 74LS151 at 4K and the 74LS368 at 5A. Problem still there. Checked the EPROMs again. They were all checking good on the programmer. Swapped out the first 2 program EPROMs. Nothing. On a whim I burned a new set of Williams EPROMs (these were Namco) and swapped out all the EPROM.
Problem fixed.


plenty plenty more here - dip switches etc etc
http://wiki.arcadeotaku.com/w/Galaga_Repair_Logs (http://wiki.arcadeotaku.com/w/Galaga_Repair_Logs)


Title: Re: Galaga rebooting over and over? Video attached.
Post by: iankellogg on April 01, 2014, 02:15:15 pm
WOrth a shot but the cross hatch being fucked up is not a good sign.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: atariforever2002 on April 01, 2014, 02:47:25 pm
My non-professional guess, you got voltage issues on the ram side of things. Had a buddy's do something similar. Had to send it to someone with a logic prob.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: iankellogg on April 01, 2014, 09:54:35 pm
Actually that is a really good point I forgot to mention. Double check your edge connector and power supply if the voltage gets a bit low it can cause lots of issues.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: Tate10 on April 03, 2014, 12:50:33 pm
Thanks for the help.  I will start with the power supply and voltages and go from there.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: ousoonerfan2006 on April 03, 2014, 01:00:13 pm
Dirty ram/roms, black tarnish accumulates on the legs of the chips and causes a lot of issues with mine, buy a can of tuner cleaner from RadioShack and remove the chips one by one and clean them.


Title: Re: Galaga rebooting over and over? Video attached.
Post by: Tate10 on April 12, 2014, 03:04:54 pm
ousoonerfan2006 that's exactly what I did and you are right the majority of the chips had a lot of black tarnish.  It works great now except in freeplay.  If I set the dip switch to freeplay it goes through a boot cycle and just keep cycling.  Switch it back to coin and it works with no problems.  Any ideas on that?  Not a huge deal I don't mind opening up the coin door and adding credits.

Thanks
Tate


Title: Re: Galaga rebooting over and over? Video attached.
Post by: ousoonerfan2006 on April 12, 2014, 09:14:27 pm
I haven't messed around much with free play on mine, I just put a credit switch behind the reject button on the coin door. I'm glad it worked out for you. I will try putting mine on free play and see what happens, sometimes you have to have certain switches on or off for free play to work or it goes into a boot cycle.