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circuit
July 6th, 2016, 01:44 PM
I noticed various Apple, Altair, Sinclair, Acorn Atom re-implementations, as well as C64 / Amiga / ST. Some FPGA, some "real" circuits. But it seems nothing relating to Commodore PET.

Now, I have ZERO skills to design something like this myself, but I can build a kit, so I would love it if something like this came along. Especially the chance to have a PET which I can attach to a monitor with an external keyboard.

Is there something particular about the PET design that has put people off doing it, or is it simply not considered interesting enough for it to be feasible?

Eudimorphodon
July 6th, 2016, 02:39 PM
Someone has already made an FPGA PET in Verilog:

http://hackaday.com/2011/10/27/recreating-the-commodore-pet-with-an-fpga/

I don't know if he's made the code for it publicly available but it's certainly been done. If you prefer something more old-school Andre Fachat has also described how to essentially replicate a PET in the form of his CS/A65 computer and a special I/O board:

http://6502.org/users/andre/petindex/hw.html

I'd say the seeming lack of interest in the PET is simply because the system completely lives in the shade of its younger cousin, the C64. From a technical standpoint the system is dead simple and any FPGA capable of handing a C64 core would have zero issues emulating a PET instead.

jac_goudsmit
July 7th, 2016, 10:34 PM
I'm working on a project called L-Star (https://hackaday.io/project/3620), which can emulate the Apple 1, the OSI Challenger C1P and should be able to emulate a PET (or a 4032 or 8032) with little or no added hardware. It would use a PS/2 keyboard and a monochrome TV monitor (PAL or NTSC). Unfortunately it can't do so at the time of this writing; It's at the top of my agenda, but I've had little time to work on the project recently.

There's nothing that makes a PET / 3000 / 4000 / 8000 series hard to emulate, it's a very simple 6502 computer with standard chips, no custom hardware. Building a replica without emulation (like the VIA/PIA and video emulation that the Propeller would do in my project) should not be hard and has been done by Andre Fachat (http://6502.org/users/andre/petindex/index.html) and possibly others, but not as kit.

===Jac

tsky
July 11th, 2016, 01:47 PM
http://www.skibo.net/projects/pet2001fpga/

The source code is up on github at https://github.com/skibo/Pet2001_Nexys3

I also have a video design that can drive a real PET display. The idea is that it could be possible to replace a motherboard with a small FPGA board.

--Thomas

gertk
July 11th, 2016, 02:30 PM
Or just use Vice on a Raspberry Pi.. Clean and simple, modern display, modern keyboard. Low power..

Storage is also no issue then..