8.2.3 Data EEPROM Code Protection

The CPD Configuration bit controls the code protection for the Data EEPROM. When enabled, external reads and writes are inhibited and a read will return all ‘0’s and further programming is disabled until a Bulk Erase operation is performed on the configuration memory region. The CPU can continue to read the memory, regardless of the protection bit settings. Self-writing the program memory is dependent upon the write protection setting.