Chen Xiao Fan wrote: >> does your ICD control the Vdd line? I don't know why, but I find that >> rather unusual that it does not. > ICd2 should be able to control the sequence of Vdd and Vpp. I'm not sure how it would do that if set to external Vdd. I regularly program boards with the ICD2 where the PIC is powered from the board. The ICD2 simply can't control Vdd in this setting. FWIW, we never had problems with programming the 16LF88 (external -MCLR) with the ICD2 in-circuit. We did have problems using a clone sold here in Brazil in this application, though. Gerhard -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist