Hi all, Forget the last post. I had an intermitent contact on the VDD leg of the 16F877. Still very strange though. I can write, read and verify perfectly on 16F84s but 16F877s won't work. It will now let me program the chip but when I read it, it appears to have filled everything with '000'. At least its a change from '3FF'. Also I can only program the chip if I erase it first. Perhaps code protection is being activated?? It sure shouldn't be..... I think I might build a Tait parallel port programmer. At least then I'll be able to use MP-LAB and program simultaneoulsy rather than doing a Windows/Linux switch everytime.... Ben -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body