The character set is a variant of ASCII, with block graphic characters and user-defined graphics in the range &80 to &A4, and tokenised keywords from &A5 onwards.

In addition, character &10 to &17 are ZX Spectrum specific screen control codes that can be used to set the current output colour, mode or position in a string either printed from BASIC or via a call to the print routines in the ZX Spectrum ROM.