> I JUST DONT GET IT.......... D120 is the number of times any one EEPROM cell can survive being written to. Once it's exceeded, that one cell may be permanently damaged, and not reliably read the data last written to it. D124 is the number of times any one cell can survive writes to OTHER cells. The high voltage involved in erasing a cell leaks a little, and erases all the other cells about one millionth of the way. Once this is exceeded, the cell may not read back the previously written data correctly, but it can still be written to (either with new data, or refreshed with the existing data) as long as its D120 limit hasn't been reached. Writing to any cell will: * add one towards that cell's D120 limit. * reset that cell's D124 limit. * add one to all other cells' D124 limit. Jason Harper -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist