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Hi there, has anyone actually ever analyzed the static (or even early dynamic PET) video timings? The ones where the video display is created by discrete hardware? I've been mulling over the schematics for the whole evening, but the use of obscure counters, JK flipflops and strange logic...

Just in case you haven't seen it, I designed and built the Micro-PET, a Commodore PET re-incarnation: https://github.com/fachat/MicroPET Commodore 2001 / 3032 / 4032 / 8032 / 8296 with options menu to select at boot Boot-menu to select different PET versions to run (BASIC1, 2, and 4) 40 col...

Hi there, there is a discussion going on on twitter about how the killer poke works and whether it actually "kills" PETs. There's actually video footage available now! https://twitter.com/AkBKukU/status/1249828043289268224 So, I'm looking for help on this forum, on any (even anecdotical)...

Hi there, I have a broken 3040 where I find that the R/W head does not fully step to the inner tracks. It seems the head uses a pin sliding over a spiral "cam activator" to be moved back and forth, and that the pin slips over the spiral back instead of following it to the innermost tracks...

Hi there, I am looking into a comparison of on-disk formats (at the low level of GCR vs. MFM etc), and also looking into the history of the drives. Apple released their "Disk ii" in June 1978, and Commodore released their 2040 disk drive for the PET in Spring 1979, with a superior on-disk...

Hi there, after recapping the 8250 disk drive in my 8296-D I decided to give it the full cleaning job. Unfortunately the keyboard fix ended really badly. One key, the "RUN/STOP" was already missing, but three more broke from the switches. I had first thought I'd be able to fix it with parts...

Hi there, recently I repaired the leaking caps in my 8250LP. When testing the drive, I found one drive ok, but the other had a high error rate on the second side. (I always get errors on the second side when formatting a disk, and I get them rather quickly - while the same disk is formatted...

Hi there, just in case you haven't heard already - it seems the 1001/8250 Matsushita disk drives in the SFD1001, 8250LP and 8296-D suffer from leaking electrolytic caps. Here is an (unfortunately German) repair instruction with pictures...

Hi there, just wanted to point you to an ongoing repair story for my B720, documented here: https://www.flickr.com/photos/afachat/sets/72157647798386959/ The current state is that it boots, but does hang on using the IEEE488 port. The next step will be checking the TPI and CIA, so I can load...

Hi there, I just wanted to share my 10MHz demo on a 9" PET4032, using my WDC65816 accelerator card. https://www.youtube.com/watch?v=ar45QJisxSg&feature=plcp Have fun! André

Hi, I have developed a new firmware for the xs1541 device. My "xd2031" plays an IEEE488 disk drive to the PET and allows to read files from the PC via serial-over-USB and a PC (currently Linux) host component. I have even already read files directly from the internet this way :-) It's...

Hi there, I was looking for a BASIC4 DOS wedge for the PET. But when looking for it, I did not really find any PET software (except what's on zimmers.net, which seems to miss some updates also). Is there a PET software repository with all the software? If not, should we create one? For example...

I've finally managed to get the PET on the "internet" - well sort of :-) At least it talks TCP/IP over ethernet now. See http://www.flickr.com/photos/afachat/5350096696/ Updates soon on my website http://www.6502.org/users/andre/index.html Cheers, André

Hi, I am repairing a PET 3032, with a broken CRT monitor. I was able to take a picture of the resulting screen - see here http://www.flickr.com/photos/afachat/5152187967/ The board itself is ok, I checked it in another PET. If you look closely you can actually see the flashed on cursor in the...

Hi there, I am in the process of repairing a 9" 4032 PET (you might have seen my question about the 12" screen on a 9" PET) The current status that the display on the screen is stable, but the characters are all missing the bit 2 (value 4). So the login message "COMMODORE" becomes...

Subject says it all basically. I have a broken 4032 (9" model, no CRT) and I think the screen is broken. It does not heat up and nothing is shown. The CPU however is working (to some degree at least, I've scoped the pins, and the screen output also looks all black except for a very small part -...