forked from Apple-2-HW/TommyPROM
9 lines
494 B
Markdown
9 lines
494 B
Markdown
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Utility to unlock 28C256 Software Data Protection (SDP) for the
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[Ben Eater EEPROM](https://github.com/beneater/eeprom-programmer)
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programmer design. This hardware is similar to the TommyPROM hardware, but it uses
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different shift register chips and different pin assignments.
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To meet the timing requirements of the SDP unlock, this code uses direct port writes
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to set and read values on the data bus. It will work Arduino Uno and Nano hardware,
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but would require changes for other platforms.
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