MLX (software)

MLX is a series of machine language entry utilities published by the magazines COMPUTE! and COMPUTE!'s Gazette, as well as books from COMPUTE! Publications. These programs were designed to allow relatively easy entry of the type-in machine language listings that were often included in these publications. Versions were available for the Commodore 64, PET, VIC-20, Atari 8-bit family and Apple II.

MLX was introduced in the December 1983 issue of COMPUTE!, with versions for the Commodore 64 and Atari 8-bit family. This was followed the next month by Tiny MLX for the VIC-20.

These versions of MLX shared a format consisting of six data bytes in decimal format, plus a seventh byte which served as a checksum. Although each line began with the memory address, and bytes were separated with commas, these did not have to be typed; the program auto-incremented the address and automatically printed the comma delimiters every three characters. Invalid keystrokes were filtered out. When a line was completely typed, it was automatically verified against the checksum value. If it matched, the user would be prompted for the next line. If not, a warning buzzer would sound and the invalid input would be discarded so that the user could retype the line. Several keyboard keys were redefined to create a makeshift numeric keypad.

MLX listings were reserved for relatively long machine language programs such as SpeedScript, while shorter programs were often printed in the form of BASIC loaders that used DATA statements to POKE the code into memory.

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