PET Datasette for NVGM CBM 4032 PET

Project revising PET datasettes
For the commodore PET 4032 I donated to the NVGM (Nationale Video Game museum in Zoetermeer) I am attempting to find a way to play a game.
Status	Initializing
Contact	mahjongg
Last Update	2024-02-09

I needed a way to load games from a datasette (commodores take on cassette data storage) I tried a SD card reader for its IEEE interface, but it did not work.

The NVGM had two datasettes, probably for Commodore C64's, but these also work for PET's, one of them was completely disassembled, bit I was told it would work fine if I cut screw it together again. the other one was flakely, but I managed to save and load a small BASIC program with it. With the other datasette I could only detect that the play key was pressed. Datasettes are the cassettedecks that commodore used for the PET 2001 the first computer that came on the market (in 1977) later that year the APPLE][ and the TRS-80 model 1 also came on the market. The commodore 1530 (CN2) cassettedeck of the PET 2001 was NOT a normal cassette player, it was especially designed to record and playback digital data. Later models had a different shape, but were (electrically) interchangeable with the original datasette.\ The first model used a 6-pole edge connector on the inside of the PET, and were addressed as device #1, later models of the PET that did not have a built in datasette had the datasette device #1 moved to the back, so a datasette connected to such a PET still was addressed as device #1 The internal connection became device#2..

I found four similar screws for the disassembled datasette. I cleaned both datasettes with windows cleaner, oiled the datasettes with penetrating oil, cleaned off old oil and checked the mechanisms, and the rubber belts. I did not find an electric problem (broken wire and such) in the disassembled datasette, and I cleaned both six pole connectors with Isopropyl alcohol.

I assembled the second datasette, and modified the cover, as it was damaged and was no longer possible to load a compact cassette in the drive then close the lid. It is now possible to remove the lid, insert the compact cassette and put the led over it.

I will test both datasettes with my own PET a 8032 (80 columns PET with BASIC 4).

So I bought a SD2PET SD Card storage for the Commodore PET / MiniPET from TheFuturewas8-Bit (TFW8b.com) but somehow it only works on my 8032 PET not on the CBM 4032 PET of the museum It is possible it doen't work on early PETs with BASIC 1 (basic on the CBM 4032 does not indicate a version, but the newer CBM 8032 indicates it has BASIC 4, that is why I am trying to get the 4032 to work with datasettes. I can create compact cassettes with games and such on my own CBM 8032, and take them to the museums PET. I.w using the better looking datasette with the NVGM PET, and use the re-assembled datasette with my own CBM 8032 with BASIC 4, that works with the SD2PET.

for now probably only BASIC games, I do not yet know how to write machine code games to tape.

The re-assembled datassette did not work, and I could see why, the left spindle is sunk lower into the deck than the right one, so I too it back to revspace, and unscrewed it with the four screws. to have a look at the mechanics of the left spindle I had to remove the PCB with the electronics. and that happened to be a big problem, the head of the screw was completely worn off,and removing the screw was impossible it seemed the spacer that should have been riveted fixed turned so it was impossible to unscrew the screw even with a good Philips head. So I used a Dremel to remove the head. after I lifted the PCB I could see why the spindel was not at the same height, the metal onto the spindel was riveted was bent, so I bent it back. and screwed the PCB back with just one screw, and made sure the thick wire of the connecting cable was soldered to ground which I found out it wasn't earlier, the probable reason why the datasette motor did not run. so this is how it looked like after the repair:

wednesday 25 january datasette still does not work

Unfortunately testing revealed that the "repaired" datassette still does not work, it can rewind, but not wind forward, and it cannot play or record. The solution (for now) is that I replaced the CBM 4032 which I could not get any game for, with my other PET, the CBM 8032, which is a little bit less authentic, and whic cannot run many PER 2001 (or CBM 4032) software. as it has an 80-columns display instead of a 40-column display. but most museum visitors will not know this, and it works with the SD2PET. I found two games on the SD that came with the SD2PET the very first game on the card worked, it is the PET version of the famous ZX-81 game "monster maze", and it seems to be converted especially for the 80 column screen of the CBM8032. The other game is PETFROGGER.

Friday 9 February devised a new use for the broken Datasette

Now that the broken datasette appears irrepairable I thought of another use for it. I'm planning to build an SD2datasette device, a plugin for the datasette port of a PET VIC or C64 that works like the CASDUINO, but for a datasette port. I can built one into a datasette in the dataette, and put the display below below the transparent ejection lid, and put its buttons below the display. And use the datasette cable for the connections to the arduino. I leaned that you can buy the PCB for it at PCBWay.