Xiaofan Chen wrote: > On 6/29/06, Wouter van Ooijen wrote: > >>>> Stef, I hope you do have decoupling cap(s) (at the very >>>> >>> least one 100nF) >>> >>>> on the power pins directly at the target chip? >>>> >>> hi Wouter, I didn't .... >>> >> Just remember to try this when you run into (other) trouble. I dunno >> whether your 25 cm would cause a problem or not, but I certainly had >> reports that omitting the decoupling at the target caused problems. >> >> Wouter van Ooijen >> > > The bypass capacitor and cable can be the issue here. I had problems > with 18F4550 with xwisp2/Wisp628 when I was testing xwisp2 beta versions > last year. Adding the bypass capacitor and shortening the cables solved > the problems. > > This problem affect PICkit 2 and ICD2 as well. Now I am using a > universal programming adapter where the bypass capacitors are > already in. The picture of the adapter is here: > http://www.pic16.com/wzcapi/mcd2/ad01.jpg > It also seems to solve problems when programming the PIC16F88. The clue was that ICSP connections always worked perfectly, but when programmed on the ZIP socket, the failure was high. No, the PGM pin was pulled down. 0.01uF seemed to do the trick. --Bob > Here is one related thread. > http://forum.microchip.com/tm.aspx?m=170399 > > Regards, > Xiaofan > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist