I have tried unsuccessfully (sp?) to erase some 16f627a and 16f628a without luck. With a picstart plus (ver 3.11) I've tried mplab 6.30 and the older 5.xx mplab ide's, and the one with beta support for this parts(6.22), the latest 6.30 doesn't support it. I've even hacked up a programer with a 16f84 connected only to the16f627a, and nothing, they won't erase. I've tried the algorithm of the 16f627 (no "a"), it programs ok, but doesn't erase. The programming algorithm datasheet says "preliminary" but they are already in production and i'm stuck with dozens of them to update, but i can't do it because they are unerasable. If anyone has an algorithm that has been used sucessfully to get a blank part please post it. Otherwise all i'm left is to try buying an icd2, (that i can't afford now) before the weekend (it apparently supports it). Also let me know if the icd2 erases this chips ok. Other info: chips were programed with lvp disabled and i have rb4 grounded.