BrianG
Member
Hello all!
Been lurking awhile, finally posting to ask a question. New to vintage computers in the last year, new to electronics. Enthusiastic about both!
I have a Commodore CBM 8032 that I purchased several months ago. I know nothing about this unit's history. From my first day with it, it would power on, make the initial beeps, and the screen would come on going directly to all forward-slash characters. No garbage-screen before that. Ten minutes pass, nothing changes. Keyboard entry does nothing. Spent the weekend, tearing the whole thing apart and cleaned it up nicely, hoping that maybe that would be enough to do the trick. It was very dirty so why not. Got it all back together, and it shined up nicely. There are 3 chips that are removable, I removed them and reseated them. Fired it back up an no change. Powers on, initial beeps, screen goes straight to all forward-slashes. Actually, I think they are forward-slashes separated by spaces. Top to bottom, left to right, screen filled with slash, space, slash, space, etc.
Looking at the mother-board, all the chip pins seem to be in really good condition, except for one chip at the UE12 location, which has a bit of corrosion but not seemingly so bad as to make it inoperable. The board is a Universal Dynamic Pet 8032089, though on the bottom side of the board it says 8032090.
So I am wondering if anyone here has any theories on what may be the problem. From poking around online, it seems that maybe one of the ROM chips could be bad? Bad RAM? Is there a way to test the chips without desoldering each one, one at a time? Any way to narrow down the possible problems? Could it be something else altogether? And besides that, does anybody have a link of a schematic for this particular motherboard? I can't seem to find one, that is legible, for this board. One that displays what each chip is, each capacitor, etc.
If anybody takes a moment to respond to this thread, thank you in advance, and please dumb it down for me a bit. I am new to this, but eager to learn. I've got a soldering iron, a voltmeter, and a buddy with an oscilloscope.
Happy New Year!!!
Been lurking awhile, finally posting to ask a question. New to vintage computers in the last year, new to electronics. Enthusiastic about both!
I have a Commodore CBM 8032 that I purchased several months ago. I know nothing about this unit's history. From my first day with it, it would power on, make the initial beeps, and the screen would come on going directly to all forward-slash characters. No garbage-screen before that. Ten minutes pass, nothing changes. Keyboard entry does nothing. Spent the weekend, tearing the whole thing apart and cleaned it up nicely, hoping that maybe that would be enough to do the trick. It was very dirty so why not. Got it all back together, and it shined up nicely. There are 3 chips that are removable, I removed them and reseated them. Fired it back up an no change. Powers on, initial beeps, screen goes straight to all forward-slashes. Actually, I think they are forward-slashes separated by spaces. Top to bottom, left to right, screen filled with slash, space, slash, space, etc.
Looking at the mother-board, all the chip pins seem to be in really good condition, except for one chip at the UE12 location, which has a bit of corrosion but not seemingly so bad as to make it inoperable. The board is a Universal Dynamic Pet 8032089, though on the bottom side of the board it says 8032090.
So I am wondering if anyone here has any theories on what may be the problem. From poking around online, it seems that maybe one of the ROM chips could be bad? Bad RAM? Is there a way to test the chips without desoldering each one, one at a time? Any way to narrow down the possible problems? Could it be something else altogether? And besides that, does anybody have a link of a schematic for this particular motherboard? I can't seem to find one, that is legible, for this board. One that displays what each chip is, each capacitor, etc.
If anybody takes a moment to respond to this thread, thank you in advance, and please dumb it down for me a bit. I am new to this, but eager to learn. I've got a soldering iron, a voltmeter, and a buddy with an oscilloscope.
Happy New Year!!!