ZX Interface 1

Loading files from machine code:

• shadowload.asm

Reference data

System variables

• sysvars.md

Channels

• channles.md

Hook codes

• hook-codes.md

Messages and report codes

• messages.md

Bibliography

• Master Your ZX Microdrive by Andrew Pennell
• Spectrum Microdrive Book by Dr. Ian Logan
• The Spectrum Machine Code Reference Guide by Richard Ross-Langley. Specifically part two, "Microdrive and Interface 1 Decoded" (which I think may have been written by David M. Webb?)
• The Spectrum Operating System by Steve Kramer