(BTW, if you are there, also check the star icon next to the help button on the top, for some amazing PETSCII demos.)
Edit: Maybe worth noting, the PET isn't only limited to it's built-in block character set, it originally came without sound, as well. However, it was soon figured out that there is a shift register connected to the user port and, if you connect a speaker to that pin, you can produce pulse audio at 1 MHz by this. (In "free running" mode, this shift register will rotate and its current LSB is exposed on that pin, each clock cycle. What's audible are the high/low state changes of that bit.) Commodore gladly adopted this scheme and added an internal piezo speaker in subsequent models. Still, every bit of sound coming out of the PET is a clever hack.
https://www.masswerk.at/pet/?prg=pssp&ram=32k&keyboard=games...
For some more PET games by Jim Orlando, ready to run in the emulator, see:
https://www.masswerk.at/pet/prgs/#jim_orlando
(BTW, if you are there, also check the star icon next to the help button on the top, for some amazing PETSCII demos.)
Edit: Maybe worth noting, the PET isn't only limited to it's built-in block character set, it originally came without sound, as well. However, it was soon figured out that there is a shift register connected to the user port and, if you connect a speaker to that pin, you can produce pulse audio at 1 MHz by this. (In "free running" mode, this shift register will rotate and its current LSB is exposed on that pin, each clock cycle. What's audible are the high/low state changes of that bit.) Commodore gladly adopted this scheme and added an internal piezo speaker in subsequent models. Still, every bit of sound coming out of the PET is a clever hack.