furnace/doc/7-systems/vic20.md

# Commodore VIC-20

the Commodore VIC-20 was Commodore's major attempt at making a personal home computer, and is the percursor to the Commodore 64.

it was also known as the VC-20 in Germany, and the VIC-1001 in Japan.

it has 4 voices that have a limited but wide tuning range, and like the SN76489 and T6W28, the last voice is dedicated to playing noise.

the 3 pulse wave channels also have different octaves that they can play notes on:
- the first channel is the bass channel, and it can play notes from octave 1.
- the next is the 'mid/chord' channel, and it plays notes from octave 2.
- and rather obviously, the 3rd pulse channel is typically the lead channel, can play notes from octave 3.

these channels are not referred as "square" wave channels since a technique to play 15 additional pulse-like waveforms has been discovered long after the VIC-20's release.

## effect commands

 - `10xx` Switch waveform (`xx` from `00` to `0F`)
Create VIC-20 documentation funny low-pass sound chip waves go brr 2022-03-27 01:32:29 +00:00			`# Commodore VIC-20`

lots of doc updates 2022-10-16 05:53:05 +00:00			`the Commodore VIC-20 was Commodore's major attempt at making a personal home computer, and is the percursor to the Commodore 64.`
Create VIC-20 documentation funny low-pass sound chip waves go brr 2022-03-27 01:32:29 +00:00
lots of doc updates 2022-10-16 05:53:05 +00:00			`it was also known as the VC-20 in Germany, and the VIC-1001 in Japan.`
Create VIC-20 documentation funny low-pass sound chip waves go brr 2022-03-27 01:32:29 +00:00
lots of doc updates 2022-10-16 05:53:05 +00:00			`it has 4 voices that have a limited but wide tuning range, and like the SN76489 and T6W28, the last voice is dedicated to playing noise.`

			`the 3 pulse wave channels also have different octaves that they can play notes on:`
			`- the first channel is the bass channel, and it can play notes from octave 1.`
			`- the next is the 'mid/chord' channel, and it plays notes from octave 2.`
			`- and rather obviously, the 3rd pulse channel is typically the lead channel, can play notes from octave 3.`

			`these channels are not referred as "square" wave channels since a technique to play 15 additional pulse-like waveforms has been discovered long after the VIC-20's release.`
Create VIC-20 documentation funny low-pass sound chip waves go brr 2022-03-27 01:32:29 +00:00
			`## effect commands`

lots of doc updates 2022-10-16 05:53:05 +00:00			- `10xx` Switch waveform (`xx` from `00` to `0F`)