PETSCII

PETSCII, an acronym for the Commodore PET ASCII, is a character encoding standard used by Commodore International's home computers, most notably the Commodore PET, VIC-20, and Commodore 64. It was developed by Commodore and is based on the American Standard Code for Information Interchange (ASCII) but with significant differences. PETSCII is a 7-bit encoding, meaning it can represent 128 different characters.

Key characteristics of PETSCII include its inclusion of uppercase and lowercase letters, numbers, punctuation, and control characters, similar to standard ASCII. However, PETSCII also features a range of additional characters not found in standard ASCII, such as reverse video characters (where the foreground and background colors are swapped), graphic characters for creating simple line art and block graphics, and special symbols. These graphics characters were particularly important for early home computer users creating visual displays and simple games before the widespread adoption of more advanced graphics capabilities.

The PETSCII standard was a crucial element in the user experience of these early Commodore machines, allowing for text-based interaction and the creation of rudimentary visual elements. While its use was largely confined to the Commodore ecosystem, it played a significant role in the development of personal computing and home entertainment during the 1980s. Modern emulators and software still often support PETSCII for compatibility and nostalgic purposes.