Ben,

Are you aware about this errata on the PIC18F2220/2320/4220/4320 devices?


Module: Data EEPROM
-------------------
When writing to the data EEPROM, the contents of
the data EEPROM memory may not be written as
expected.

Work around:
------------
Either of two work arounds can be used:

1. Before beginning any writes to the data
EEPROM, enable the LVD (any voltage) and
wait for the internal voltage reference to
become stable. LVD interrupt requests may be
ignored. Once the LVD voltage reference is
stable, perform all EEPROM writes normally.
When writes have been completed, the LVD
may be disabled.

2. Configure the BOR as enabled (any voltage).
Select a threshold below VDD to allow normal
operation. If VDD is below the BOR threshold,
the device will be held in BOR Reset.
Date Codes that pertain to this issue:
All engineering and production devices.


Ben what is you silicon revision of that part?

Regards,

Ken Pergola

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