Got a Vader

[Trinity]

I bought a lot of two vaders (as is) for $7 bucks on e-bay. One has some serious problems, It acts like the cartrige port is dirty. But no matter how many times I try, it won't work,,, just a scrambled picture. (what causes this problem)? And it has a broken pin on the left controller port. Pin one, BTW. Is pin one very critical?

 

The other working one's case was almost fubar... And it's working mobo was rusted and it's case looked like it was sitting in a muddy leafy garage for the last 20 years.

 

Took the best of both units to build this. I guess I'll use the other one for parts.

 

Three hours cleaning and rebuilding later.

Edited July 9, 2009 by Trinity

[MasterESGT]

Check for bend pins of cartridge port, if you get alway a scrambled picture maybe some pins are bent and no contact is made. If not, try gigling the cart and power off-on again, probably dirty pins. Scrambled picture and weird steady sound means that a data and/or address pin is missing.

 

The controller port pin 1 is the UP signal, means that without this pin you'll not be able to move UP (but no mather if game control is left/right only like Spider Fighter).

Edited July 9, 2009 by MasterESGT

[Benzman66]

Sounds like one of the CPU chips went bad. Swap each one out at a time with the working unit and see if it fixes the problem.

[Trinity]

Sounds like one of the CPU chips went bad. Swap each one out at a time with the working unit and see if it fixes the problem.

 

Ok, cleaned the cartrige port, No change on the scrambled picture problem. I got into the RFI cage and checked the 3 main IC's, they are socketed and look very well seated. No corrosion to be seen. Pressed them down and wiggled them, Still a garbled picture. What chip is most likely to be bad? TIA? RIOT? or 6507?

 

I can't swap chips yet... I need an IC extractor first.

Edited July 12, 2009 by Trinity

[Spazmonkey]

Or a flathead screwdriver.

 

Seriously? Just poke a screwdriver under there and lift them up.

[Trinity]

Or a flathead screwdriver.

 

Seriously? Just poke a screwdriver under there and lift them up.

 

Ok... I could do that...

 

But what ic first please.

 

 

TIA? RIOT? or 6507?

[channelmaniac]

I'd go RIOT first then 6507... and TIA for last.

 

RIOT = RAM, I/O, and Timer. Without RAM you get squat. Without CPU you get squat. But in either case you'll get lines and random stuff on the screen.

 

RIOT is usually the first to go since it controls the sticks and other things.

 

RJ