# Commodore VIC-20

the Commodore VIC-20 was Commodore's major attempt at making a personal home computer, and is the precursor 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.** range is `00` to `0F`.

## info

this chip uses the [VIC](../4-instrument/vic.md) instrument editor.

## chip config

the following options are available in the Chip Manager window:

- **PAL**: 1.10MHz instead of 1.02MHz.
- **Disable filtering**: bypasses the hardware's lowpass filter.