Remembering the Commodore PET 2001
Don't trust anything over 1MHz
This Old Box Bah. Kids today with their Nintendo Wiis, iMacs, 30-inch HDMI screens, PDAs and CD-Romses.
Back in the Golden Years of electronics, personal computers required a Master's degree or a crippling social disorder to operate and it was better that way.
And colors? You had two options: stunning beige or get the hell out. The Register is proud to be a favorite for a healthy stable of crotchety old tech geezers, and in their honor, we're looking back at the kit of yesteryear and giving it a tearful salute. Oh, it tastes so salty!
Over the next few weeks, we'll retrospect some of the computers that made the industry what it is today. Our first peek hearkens back to the 1970s, when PCs were just becoming P.
Commodore P.E.T. 2001
OS: BASIC in ROM
Processor: 1MHz MOS Technology 6502
Memory: 4K, 8K
Display: 9" with 40x25 text
Storage: Built-in cassette
Ah, the Commodore Personal Electronic Transactor. Finally users could...transact at the comfort of home.
This device, released in 1977, is often regarded as the first all-in-one computer. It's not Commodore's first effort: they released the KIM-1 beforehand — but that system was all kit and no caboodle. The KIM-1 also used an out-of-house chip design they bought from MOS Technologies.
MOS had been playing second banana to Texas Instruments selling calculator chips before the market collapsed due to manufacturing expenses. The company was rescued from ruin by Commodore in 1976 when they bought the entire company on the condition was that Chuck Peddle would join the company as chief engineer. MOS would become the Commodore Semiconductor Group, although their chips would continued to be stamped with the old MOS logo until 1989.
In his new position, Peddle convinced Commodore that calculators were yesterday's news. The company should instead focus on the burgeoning personal computer market and expand on the KIM-1. The result was the PET 2001, using the MOS Technologies 6502 CPU, which would later find its way into many other computers of the age.
The first model was PET 2001, which sported 4KB of 8-bit RAM (later 8KB was offered in the 2001-8 model). The machine was similar to the KIM-1, but with a 9" monochrome monitor attached. It was also one of the few computers with a built-in cassette drive:
Unfortunately, this feature left little room for the keyboard. The resulting pad was often slandered as the "chicklet keyboard" due to it's diminutive size:
A look at the layout:
A later PET model used a larger keyboard, but the cassette storage was made external. The newer model had better success on the market — leading Commodore to introduce the system to Europe. Dutch firm Philips however, had already released a machine called PET in Europe, resulting in a name change to the CMB (Commodore Business Machines) 3000 series.
Thanks to the Computer History Museum in Mountain View, CA for letting us take pictures of your systems. We didn't touch, we swear.
And now, dear readers, we turn the floor over to you.®
"On The Edge" by B. Bagnall
Really good history of Commodore's Computer years.
Great insight into everything from 6502 design to the
In 1982 I won a Commodore 4000 and disk drive for my school in a competition. It was the first disk drive the school had ever owned - my maths teacher kissed me when she found out ...
Years later - about 1990 - it was surplus to requirements, and they offered it to me. These things had an IEEE488 parallel interface as standard, so they were brilliant for instrumentation, so "my" PET took on a new role doing superconductor characterisation tests in Oxford. I understand that it only retired from that about 2000.
My greatest feat was to write a VT52 (subset) terminal emulator for it, in basic. The only connection I had was done by going IEEE488 -> RS432 (current loop) with one convertor, then RS432 -> RS232 with another, then through a Gandalf box into the university network. 50 baud was pushing it.
:( I want one
first computer I ever had was the relativly new IBM PS1 (pre-HDD think it ran from a Rom chip but I could be mistaken) and I miss that shed loads.
I also had a Sinclare Spectrum but it wasn't the same :(
There was 4 of us with these. We had a contact within Commodore so upgraded our 8K machines to 64K, needed to upgrade power as well so the cassette had to go external. We developed games for the "PET" using these machines and then compiling them to get into the 8K, if we could'nt do it we had tools to shift some of the code into the input/output memory to fit, which was also a neat way to stop people copying them because as soon as they "saved" program it would overwrite the buffer memory. We also made "sound" boxes out of old metal tobacco tins with components inside and attached to the output serial port. What "geeks" we must have appeared but as all of us where IBM'ers working on "real" computers it was just a social thing.
The day IBM brought out there PC we were all called to meetings with our managers and given the option of stopping work on our "hobby" or leaving IBM. Unfortunately we all made the wrong decision and stayed with big BLUE.
One thing I do remember about these were how easy it was to fix them when they went wrong. You could juggle the memory to isolate errors...
I knew some idiot would post up the poke code required to give Curators of computer museums a headache!
My excuse for not remembering the exact reason why it would go up in a puff of smoke is easy. Hey man I was only 14 at the time!
I always wanted a PET since I was 14, but of course could never afford one.
When Ferranti finally closed its doors 20 years later, I wandered around an empty factory floor seeing what I could pick up cheap.
There in a corner was an unwanted broken Pet. I had to own it! This was my very last chance of owning my first technological icon!
How much did they want for it?
I pay a fiver and it sat in my living room staring back at me for a further 3 years before I gave it to a loving museum. (I got married).