Inside the PET Keyboard [Hackaday]

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These days, you have a certain expectation for computer keys on a keyboard. Of course, there are variations and proponents of different mechanisms and noise levels. However, back in the late part of the 20th century, it was a different world. Computers came with a bewildering and sometimes befuddling array of keyboards. Since the IBM Selectric was the king of typewriters, we assumed the IBM PC keyboard would be spectacular, but it wasn’t. The PC Jr was even worse! Atari experimented with flat keyboards to save costs, and many computers had keys more reminiscent of calculator keys than you would imagine. The market voted. In general, a keyboard that wasn’t really a keyboard was the kiss of death for a computer. Case in point: the Commodore PET with its infamous chicklet keyboard, which gets a detailed examination in a recent post from [Norbert Landsteiner].

The PET keyboard gets some bad rap due to software limitations. Because of this, some games would use their own scan routines, and [Norbert] has worked on emulation able to accommodate software that wants to read the hardware directly. The resulting insights into the old keyboard is very interesting. For example, you can press more than one key at once. The result? The answer to that question takes up about half the post.

Now that our keyboards have their own CPUs and send serial data to the main processor, it is easy to laugh at these old designs. But the machines that could do more with their CPUs cost less, and that was important in a world where CPUs didn’t cost a few dimes each. Ironically, these days our CPUs run at 100 times the speed, yet we rarely ask them to do all the work these old computers required to operate.

By 1979, the PET graduated to a more conventional keyboard, but until then, users suffered with the tiny keys. Reliability was poor. The legends tended to wear off quickly, too. The post covers some of the later keyboards, too. If you are a PET fan, or you just want to peek under the covers of a classic old machine, it is well worth the read.

The PET can, however, play YouTube videos at 30fps. Really. They showed up in some odd places, too.