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Arcade and Pinball Discussions => Beginner's Help Corner => Topic started by: wantsomemuffins on December 12, 2015, 04:49:41 pm



Title: Graphical issues with score and title screen
Post by: wantsomemuffins on December 12, 2015, 04:49:41 pm
Hello, I have recently been given a Time Pilot arcade cabinet as a gift and I was started to clean it up and try to restore it to a presentable point. One issue that it seems to have is a graphics issue with the score at the top of the game, the ship sprites at the bottoms of the game and the title screen being all pixelated and corrupted (if that is the word I should be using). Besides those issues the game is playable and everything else shows up fine. Is there anything I could do to correct this? The pictures can be seen here. http://jakenslagle.imgur.com/all/ (http://jakenslagle.imgur.com/all/)


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 12, 2015, 11:08:43 pm
Well i can't see your photos because you have your account set as private.

I'm not sure what is going on until I see the photos.


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 12, 2015, 11:10:44 pm
you should be able to see now


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 12, 2015, 11:12:58 pm
Okay the best I can think is going on is the sprite eproms are bad or not making good contact.

Try removing each eprom and putting it back in and inspect for bent legs while you have them out.


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 12, 2015, 11:15:29 pm
I am new to arcade cabinets, but I am good with electronics in general and working with physical components of computers. What should I be looking for and where would it be located?


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 12, 2015, 11:18:19 pm
on the game PCB, which is probably in a cage inside the cab.

The PCB for time pilot is a two board stack and the eproms are on the bottom PCB. you will have to remove the screws and take the boards apart. The sprite eproms are pretty much right in the middle of that board. Pretty much anything socketed should be removed, inspected and replaced. This potentially wipes the contacts clean and allows you to inspect for broken or bent legs.


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 13, 2015, 02:59:24 pm
I took out and inspected all the eproms and only one looked out of the ordinary it has corrosion on all of the legs. Could that possibly be the problem? How would I go about cleaning?


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 13, 2015, 03:03:41 pm
I use a brillow pad and lightly rub the entire side of the eproms on that. I doubt that is the cause but it never hurts to do it. You could just have bad eproms. Or something else going on. Any chance you could post a photo of that bottom pcb here.


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 13, 2015, 03:13:27 pm
Here are a few pictures I tried to get the focus as best as I could. http://imgur.com/a/e51CG


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 13, 2015, 03:16:25 pm
Good it's not a bootleg


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 13, 2015, 03:26:03 pm
Yup, now what do you think I should try?


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 13, 2015, 03:29:43 pm
The only other easy fix would be to test the eproms. Which you need a burner for.


Title: Re: Graphical issues with score and title screen
Post by: wantsomemuffins on December 13, 2015, 03:32:58 pm
Ok so I 'll just have to live with it then?


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on December 13, 2015, 07:12:45 pm
Well I mean you could fix it. The first instinct with what I see is a bad eprom. All the text data is stored on one eprom and that is what seems to be missing.

Easiest option is of course to check the eprom in a burner but you can always just try a new eprom.


Title: Re: Graphical issues with score and title screen
Post by: oscar-hernandez1983 on March 13, 2016, 09:40:21 pm
I have the same problem with my dirt dash arcade may be the eproms like you said I just have a find a way to test them


Title: Re: Graphical issues with score and title screen
Post by: iankellogg on March 14, 2016, 09:50:48 am
You will need to find someone with a eprom burner or buy one yourself. you can get them for like $30 and a good one for $100. I recommend the $100 GQ-4X as it has the widest support available.