ZX81 is a Sinclair Research computer released in 1981. It has no sound, 1Kb of memory, and black&white (monochrome) graphic in hardware resolution 64x48 pixels. BASIC is its main operating system, working on Zilog Z80 CPU 3,5Mhz. The newest device for ZX81 users is ZXpand invented and developed by SirMorris and being sold by RWAP Software. The ZXpand gives to our ZX81: - 32Kb of RAM, - flash (instant) loading/saving of programs, - SD card as an easy data-transfer with PC, - sound of AY chip (nowadays it's mostly Yamaha YM2149, like in Atari ST and a lot of ZX Spectrum machines), - joystick port (in the AY module), - the port mentioned above is also a port for mouse (also in standard of Atari ST). This demo has been made for ZX81 with ZXpand with AY-module. It's only BASIC, in a joke convention rather, but still - actually it shows for real coders what could be possible to do with the mentioned full hardware combo, if even such a bone-head like me could do anything bearable.
