What about the 16C77x's with the ability to rewrite program memory from code? Do they have more enduring EEPROM for both program and data memory? Tom. ----- Original Message ----- From: root Subject: Re: Retaining User Settings In EEPROM > > > The two EEPROM spaces are different. On a F84, the data EEPROM includes > > > an error-control system so it will be millions of writes before it is > > > very likely that data will not be stored correctly. The program EEPROM > > > doesn't have this feature so it will fail sooner. Since the program > > > EEPROM can only be changed in a chip programming setup, Microchip > > > doesn't expect it to be written very many times.