Hi, I'm working on a PIC16C84 programmer project. All programming commands given in DS30189D documentation from Microchip are working fine except for "BULK ERASE PROGRAM MEMORY" and "BULK ERASE DATA MEMORY" witch are 001001 and 001011 respectively. For example, in chapter 2.3.1.8 (BULK ERASE PROGRAM MEMORY) the doc says: 1- Do a "Load Data All 1's" command 2- Do a "Bulk Erase User Memory" command 3- Do a "Begin programming command" 4- Wait 10 ms to complete bulk erase so, my programmer send: 1- 000010 0111111111111110 2- 001001 3- 001000 4- wait 10 ms When I read back the chip, no location of the Prog Mem changed, am'I missing something or is there some mistakes in DS30190D. Any idea ? Note: I can do the equivalent operation by writing 3FFF in all program memory locations but this consumes much more time. Thanks for your time and attention. ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com