>At 09:50 15/06/98 +0200, Jim robertson wrote: >Ha! What a joke. They told you the difference was EEPROM Versus FLASH! >There is no difference BECAUSE THE 16F8X ARE NOT "TRUE" FLASH DEVICES!!! >Microchip are being misleading (They are not the only chip manufacturer >calling EEPROM "FLASH" though. Atmel, I believe also do it) On the contrary! It looks very much like the 16F8X are true FLASH devices while 16C84 was a true EEPROM device. Now, I do not know on what premises or information Jim is saying 16F8X is not true FLASH. It may be helpful to make it clear what is the difference between an EEPROM and a FLASH. The difference is not only that between a byte erase and a block erase even though this is a consequence of the design. You may have an EEPROM with only a block erase. The most important difference is the memory cell design: in EEPROM you have a two transistor cell, in FLASH there is only one (FAMOS) transistor in one bit memory cell. Therefore the silicon area of the program memory in a FLASH device is smaller and that is one possible source of the extra chip area the designers had and thus were able to double the size of the register file. I know that 16F84 has to be erased prior to reprogramming which is indicative that the memory cell is not rewritable. I would like to hear what happens with a 16C84 part? Do you have to erase it or does it erase byte by byte while being programmed like an EEPROM does? If you have a bit pattern 10 and you reprogram 01 do you end up with 11, 00 or 01 in the place? 11 or 00 means no byte erase while 01 means the byte erase is possible and therefore you have a two transistor cell which necessarily means an EEPROM. -- Lauri --- For more info.