Desperado
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g10 pin 6=pulse
g10 pin 8=pulse
g9 pin 8=pulse
g9 pin 9=pulse
e11 pin 7=pulse
e11 pin 9=pulse
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Commodore pet 3032 screen full of lines
- Thread starter Desperado
- Start date
g10 pin 6=pulse
g10 pin 8=pulse
g9 pin 8=pulse
g9 pin 9=pulse
e11 pin 7=pulse
e11 pin 9=pulse
Dwight Elvey
Veteran Member
That is good easter eagging but not good trouble shooting for reference to others. It would be better to finish trouble shooting with Dave for others looking at this thread. I suspect your right, blowing a set of ROMs will likely help. What do you mean by double screen?
Dwight
Desperado
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Double screen cause pettester show 2 alternates screen
Dwight Elvey
Veteran Member
I guess I have to be a Pet person to understand. Nice to have an alternate screen.
daver2
10k Member
>>> Double screen cause pettester show 2 alternates screen.
No idea what you are talking about?
Ok, with the PETTEST ROM in the kernal ROM socket you are getting video. Is that what we are saying? There is a small probability that the video screen had been erased completely but the code has crashed befor it has had a chance to display any meaningful characters on the screen. My test process would have identified that scenario if you had followed through with it...
The 'first' screen indicates that page zero RAM is all bad/faulty (hence the b's). You need to explain further what the other screen of garbage is that you have shown. Does it alternate with the screen of b's? If so, at approximately what frequency?
Dave
No idea what you are talking about?
Ok, with the PETTEST ROM in the kernal ROM socket you are getting video. Is that what we are saying? There is a small probability that the video screen had been erased completely but the code has crashed befor it has had a chance to display any meaningful characters on the screen. My test process would have identified that scenario if you had followed through with it...
The 'first' screen indicates that page zero RAM is all bad/faulty (hence the b's). You need to explain further what the other screen of garbage is that you have shown. Does it alternate with the screen of b's? If so, at approximately what frequency?
Dave
Desperado
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Hi Dave,yes the other screen it alternate with "b" screen every 2 secondos more or least...
I ve also changed bad roms with new eprom and now i ve again black screen
daver2
10k Member
So, we at least know that the video circuitry appears to work.
Can you download my PETTEST code, burn it into a 2K EPROM, put it in place of the EDIT ROM and plug the kernal ROM in please. What do you see on the screen?
You'll have to lookup my google drive reference on the VCFED Commodore thread though. It is currently version 4. This is an extended PETTEST than the one that lives in the kernal ROM socket and can test the video screen, page 0 and 1 of RAM, the keyboard and ROMs and a more extensive memory test of all of the RAM.
EDIT: Here https://drive.google.com/drive/mobi...cG98a2FDOMo1H5pj9lIdJpHcx?sort=13&direction=a.
Just a thought about your double screen. Is it possible that the character generator is faulty. I know you said that you have got the correct checksum, but if it is faulty you could get a screen of capital B's that get converted into random rubbish. I do, however, have a test for this scenario if your video RAM is socketed...
Dave
Can you download my PETTEST code, burn it into a 2K EPROM, put it in place of the EDIT ROM and plug the kernal ROM in please. What do you see on the screen?
You'll have to lookup my google drive reference on the VCFED Commodore thread though. It is currently version 4. This is an extended PETTEST than the one that lives in the kernal ROM socket and can test the video screen, page 0 and 1 of RAM, the keyboard and ROMs and a more extensive memory test of all of the RAM.
EDIT: Here https://drive.google.com/drive/mobi...cG98a2FDOMo1H5pj9lIdJpHcx?sort=13&direction=a.
Just a thought about your double screen. Is it possible that the character generator is faulty. I know you said that you have got the correct checksum, but if it is faulty you could get a screen of capital B's that get converted into random rubbish. I do, however, have a test for this scenario if your video RAM is socketed...
Dave
Last edited:
Desperado
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Unfortunately now i don't have a 2716 eprom...can i burn your pettest on 2732 maybe?
Thanks
dave_m
Veteran Member
Yes, but burn the 2K code into the upper 2K address space from 0800 Hex to 0FFF Hex. In other words use a 0800 Hex block size (2048 decimal) and a transfer start address of 0800 Hex. Does that make sense to you?
Dwight Elvey
Veteran Member
With bad zero page RAM, it is not likely to do much on the video out. Almost everything needs good page0 and some page1.
Dwight
Dwight
dave_m
Veteran Member
Dwight,
daver2's Pettest3 does not rely on RAM for the RAM test, and it looks like the screen RAM is mostly working.
Desperado
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It i use this dos command "A.bin + b.bin c.bin" can i copy c.bin in 4k eprom?
daver2
10k Member
Correct.
All of the initial tests do not rely on pages 0 or 1 (the stack) to be working. All data for these initial tests are stored in the scarce CPU registers. The firmware tests pages 0 and 1 in a relatively simple manner before moving on to more comprehensive tests that do use pages 0 and 1.
Just to avoid confusion, Version 4 is the latest (and last - hopefully) that I will be producing (subject to any bugs being found).
Dave
All of the initial tests do not rely on pages 0 or 1 (the stack) to be working. All data for these initial tests are stored in the scarce CPU registers. The firmware tests pages 0 and 1 in a relatively simple manner before moving on to more comprehensive tests that do use pages 0 and 1.
Just to avoid confusion, Version 4 is the latest (and last - hopefully) that I will be producing (subject to any bugs being found).
Dave
daver2
10k Member
Just check that the BIN file is exactly 2048 bytes in size before you do the copying, otherwise the second copy won't be exactly at the right location.
The EPROM burning software should also have a facility to load a file into the programmer with a user-defined offset. In which case you can load the file twice; once with a default offset of 0 and a further second time (without initialising the existing contents of the programmer) with an offset of 2048 (decimal).
Going back a page I see dave_m has stated the same as I have. Great minds think alike..........
Dave
The EPROM burning software should also have a facility to load a file into the programmer with a user-defined offset. In which case you can load the file twice; once with a default offset of 0 and a further second time (without initialising the existing contents of the programmer) with an offset of 2048 (decimal).
Going back a page I see dave_m has stated the same as I have. Great minds think alike..........
Dave
Desperado
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Hi Daver2, i putted your Pettester4 on ud8 with other roms inserted and i have this:
https://youtu.be/efqoSNxEjLw
I have also tried with another char rom but it's sam thing....
Thanks
daver2
10k Member
Page 0 and 1 RAM is all faulty...
Forget the character ROM at the moment.
Is your main RAM socketed or not?
Can you also check with your logic probe that you are getting pulses on UB2 pin 8 (7425) please. This should indicate that RAM is being selected.
Dave
Forget the character ROM at the moment.
Is your main RAM socketed or not?
Can you also check with your logic probe that you are getting pulses on UB2 pin 8 (7425) please. This should indicate that RAM is being selected.
Dave
Last edited:
Desperado
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Desperado
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daver2
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No, please don't start desoldering things on a whim please.
I added a bit more information to my previous post for you to check a pin out.
Let's see if we are getting correct reads and writes.
>>> Can i check Ub2 with pettester inserted?
Yes, in fact, I don't want you to remove my PETTEST until told to.
Dave
I added a bit more information to my previous post for you to check a pin out.
Let's see if we are getting correct reads and writes.
>>> Can i check Ub2 with pettester inserted?
Yes, in fact, I don't want you to remove my PETTEST until told to.
Dave
Desperado
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