XEGS Issues

[blowback]

I have a XEGS that is staring to give me issues with the built in Missile Command. I'm starting to see graphical glitches, and every once and awhile it will just freeze mid-game. I've gone through the internal tests, and everything passes. What should I look at next?

 

 

Thanks.

 

[Justin Payne]

Have you run any of the diagnostic carts?

[blowback]

Have you run any of the diagnostic carts?

 

 

Not yet. Will add one to my next order and see what happens.

[+Nezgar]

I read a previous thread that just the C101687 ROM chip was bad, and was fixed by simply replacing with an EPROM, but his issues exhibited problems in the Self Test too...

http://atariage.com/forums/topic/275050-xegs-rom-error-test/?p=3950736

 

Usually most chips are soldered directly to the motherboard, but some may be socketed, like GTIA? Maybe if you crack it open see if any are socketed chips, and remove/reinsert the chips if it helps.

 

A 27256 EPROM is a direct replacement of the OS/BASIC/Missile Command ROM, but you'll probably have to cut it out and install a socket too. I'd be happy to program and send you a EPROM if you like... (just noticed you're in Calgary, easy from Regina!)

 

the RAM is also only 2 chips, also attainable from BEST or eBay, but again you'd have to probably socket the locations.

[+Nezgar]

Another thought... check the voltage output from your power supply. Anything more than 5.2V-5.3V under load is risking damaging the IC's. Under 4.7V starts affecting the colour, and maybe other instability, but is much less likely to cause permanent damage.

 

Here's an Atari power supply reference graphic I like, courtesy of Eight Bit Fix

 

The 'Ingot' (top row middle) fails by outputting as much as 9-11V, and is notorious for damaging systems.

[blowback]

That’s awesome. I should have time to check a few things this weekend.