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PET index - versions

What different machines are there? Version Overview

The Problem that caused much confusion is that there are a real lot of different versions of PET-type computers. PET-type, as in Europe they are called `CBM' machines, not `PET', and had a different numbering. Here is only an overview with some comments. For more information look at the petfaq.

There are 4 major case versions:

  1. 9" design model, never sold
  2. 9" screen and tape recorder builtin, small chiclet-type keyboard
  3. 9" screen builtin, full-size keyboard (with or without graphic symbols)
  4. 12" screen builtin, full-size keyboard (with or without graphic symbols)
  5. 12" turnable screen builtin, separate keyboard, rounded case, business keyboard

All except the "separate keyboard" are one-piece cases. Pictures of these cases can be seen in the PET gallery.

In addition to that there are 4 major board revisions (see the boards section) And also the ROMs have changed too.

Model Numbering

This can also only be an overview, for more accurate numering information please look at the CBM products list. All models except 80** and the SuperPET are 40 columns.

Comments

I guess to understand this numbering one has to understand a bit of the model history. First the 9" models with board #1 and built-in tape have been developed. The hardware was pretty much ok, but the software was buggy. (Don't know if these boards have been sold with full-size keyboard).

Then they improved the software to BASIC 2 and working IEEE488, as well as they developed the #2 board. They were also made for the 9" cases, They were available with full-size keyboard (with tape as well? don't know).

After that came BASIC 4, with the 4000 series.

However, as the first BASIC version was so buggy, a lot of machines were upgraded to higher BASIC versions, and the 9" models were even sold with Basic 1, 2, and 4 (probably as 2001, 30** and 40** models). That is why there are so many different types.

When Commodore developed the CRTC board (#3) they first did a version for 80 columns only. This probably went along with the development of BASIC 4 (?). So they sold 9" 40 columns PETs with BASIC 4 without CRTC, and 12" 80 columns PET with CRTC and BASIC 4.

Then they modified the 80** board to the "universal dynamic PET board" to be able to display 40 columns as well. It only fits into the 12" case, so the "fat-40" with 40 columns and CRTC was born. I.e. they sold 12" cases with basically the same board as 40** and 80**, which supposedly reduced production costs a lot.

This universal board then became the base for the SuperPET and the 8096, which were actually add-on boards to the 8032 board, either with an additional 6809 CPU, RAM and ROM, or with a simple 64k RAM extension.

CBM then designed a new case, the rounded separate keyboard case. Unfortunately the 8032 boards didn't fit in there, so they improvised something with a lot of wiring.

Finally CBM designed the new board with up to 128k RAM. This board is used in the rounded separate keyboard cases, and reduces the I/O to $E8**, so that $E900-$EFFF can be used for nationalized editor ROMs. I have to see reports about other models than the 8296 to use this board actually.

More on the PET history can be found on the Commodore.ca web site.


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PET index V1.0 (c) 1998-2005 A. Fachat