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EEPROM.md

EEPROM

Device Description

An EEPROM that can be built into various devices to store supplementary data. Holds 8 words, that can only be read or written a single word at a time.

Interrupt Commands

All interrupt commands are done with A set to 0xFFF0, sent to the same device as the EEPROM is attached to. Register B is used to select the command, and X and Y are used for address and data.

  • 0x0001: READ
    • Reads word from address X and stores it in register Y.
  • 0x0002: WRITE
    • Writes word from register Y to address X. Note that writing to the EEPROM can only clear bits, not set them, so you may need to clear the EEPROM to write new values.
  • 0x0003: CLEAR
    • Clears all words to 0xFFFF
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