Editing Programming an EEPROM with HEX files (section)

== Common failures ==

{| class="wikitable"
! Symptom !! Likely cause
|-
| Stuck on <code>Connect EEPROM</code> || EEPROM not seen on I<sup>2</sup>C.  Check wiring and that the chip answers at address <code>0x50</code>.
|-
| <code>BAD LINE COUNT</code> || Not 129 lines (single slot) or 1025 lines (<code>all.hex</code>).
|-
| <code>BAD ADDR RANGE</code> || The HEX addresses do not match the expected range for that slot.
|-
| Red blink at startup || I<sup>2</sup>C bus locked, or no EEPROM present during the initial scan.
|-
| File copied, nothing happens || The file is a dotfile, is zero bytes, or was already processed this session.
|}

A zero-byte HEX file is ignored but still marked as processed.  This is how the editor's '''Clear Hardware''' button works — it writes empty files over the slots.

macOS users: Finder likes to write hidden <code>._</code> companion files onto removable drives.  The programmer ignores dotfiles, so these are harmless.