Commodore 64 Black Screen :(

[revolutionactiondk]

Anyone in here who is good with Commodore 64?

 

My breadcase is only showing a black screen, much like the one you get in between when you turn on your C64 and waits a sec for the blue Basic startscreen to appear.

 

So there IS connection to the RF cable as the screen turns black - but not into the "blue screen"

 

 

I really hope it is a typical error I can fix and sod myself ... PLEASE help.

[bigbee99]

Outside of a dead test cart I don't know a lot to help you. Does the A/V output still work? That would tell you if it's a comp or a problem with the RF. Here is you some help if you are unfamiliar with that port.

 

1, Luminance Black

3, Audio Out White

4, Video Out Yellow

6, Chrominance Red

2 ground

[bigbee99]

There is also Ray Carlsens page.

 

http://personalpages.tds.net/~rcarlsen/cbm/c64blank.txt

 

He's full page can be seen here.

 

http://personalpages.tds.net/~rcarlsen/cbm.html

 

It suggest it could be a problems with the power supply, among other things. You could check the PS with a multi meter. Need the pin outs for your PS? Got a link for that too

 

http://www.hardwarebook.info/C64_Power_Supply

 

B

Edited July 10, 2011 by bigbee99

[revolutionactiondk]

Outside of a dead test cart I don't know a lot to help you. Does the A/V output still work? That would tell you if it's a comp or a problem with the RF. Here is you some help if you are unfamiliar with that port.

 

1, Luminance Black

3, Audio Out White

4, Video Out Yellow

6, Chrominance Red

2 ground

 

Dead test card? Don't know what that is

I think the A/V works. But it only shows the black screen. You know, the screen turns from flicking/noize to a black screen when I turn it on. So it does get and show a signal. It is just completely black instead of the normal boot screen.

[AtariGeezer]

 

My breadcase is only showing a black screen, much like the one you get in between when you turn on your C64 and waits a sec for the blue Basic startscreen to appear.

 

It could be a bad VIC-II chip, do you have another 64 you can swap chips with?

 

Jay

[revolutionactiondk]

 

My breadcase is only showing a black screen, much like the one you get in between when you turn on your C64 and waits a sec for the blue Basic startscreen to appear.

 

It could be a bad VIC-II chip, do you have another 64 you can swap chips with?

 

Jay

@BibBee99 and AtariGeezer.

Thanks a lot for your help! Yes I have a spare C64 but that one is working and I am afraid to mess that one up. It is however not the cable nor the poweradaptor as my first step was to try the two C64 with the same setup/poweradoptor/RF-cabel.

 

But I will try and look at the pages and see what can be done. Thanks!

[nathanallan]

Have you tried skipping the little RF adapter, and going with strictly AV cords? You know, yellow/red/white ones? The C64 has s-video built in, so you can get a cable cheap on ebay that goes straight to s-video.

[carlsson]

Perhaps THE most common fault inside a C64 is the PLA chip, which handles address decoding. I believe one way of testing it would be a short series of very fast power on/offs to see if you get any action. See Ray Carlsen's pages as linked to above for further help.

 

This page sells loose PLA chips at $12:

http://www.oldsoftware.com/CBMchips.html

 

If you'd rather have a long-term (?) solution, here are some homemade hacks to replace a PLA with either an EPROM or a FPGA. Some people claim the EPROM solution is "nothing but trouble" but if you already have an EPROM programmer and can get ahold of some spare chips, it might be the cheapest solution.

 

http://www.zimmers.net/cbmpics/cbm/c64/pla.txt (27512 EPROM solution)

http://www.fpgaarcade.com/c64_customs.html (15 GBP = $24)

http://www.retro-donald.de/shop/pages/bakery/superpla-67.php (10 EUR = $14)

 

Good luck!

Edited July 11, 2011 by carlsson

[bennybingo]

That's what mine did back in the day when my power supply started to go. Luckily, it didn't fry my motherboard.