Have you got a 4.7uF DC decoupling cap anywhere in your circuit? I must have programmed hundreds of chips with ICSP with my PICStart Plus, and I do remember that it doesnt work with certain 4.7uF DC decoupling caps. Cheers, Shane. > -----Original Message----- > From: pic microcontroller discussion list > [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Nicholas Irias > Sent: Tuesday, 10 April 2001 5:29 a.m. > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: [PIC]: ICSP w/ PIC16F877 > > > thanks. I'll try again with no cap and see it that does the trick. > > ----- Original Message ----- > From: "Roman Black" > To: > Sent: Monday, April 09, 2001 9:58 AM > Subject: Re: [PIC]: ICSP w/ PIC16F877 > > > > Nicholas Irias wrote: > > > > > > More on the configuration: > > > > > > My programming leads are 22ga wire, about 18" (~1/2 meter) long. > > > > > > RB6 and 7 are used only for programming. > > > > > > RB3 is not used. I have tried leaving it floating and also tying it to > > > ground via a 1K resistor, but still get the same error message. > > > > > > I am not using the low voltage programming mode. > > > > > > MCLR has .01uF cap to ground. It is pulled up to Vcc via a 47K resistor > in > > > series with a diode to allow MCLR to go to 13 volts for programming. > > > > > > I think you have it there. You have a 470 ohm series > > resistor and .01uF cap RC network. Bad. :o) > > Try removing the cap totally (bst), or shorting > > the resistor. > > > > Microchip are sketchy about the actual timing > > the Picstart uses for MCLR (RESET->VPP) > > and I think the program and verify timings are > > different. You may be getting good programming > > and bad verifying. Either way you need to mod > > that cap so MCLR can get to VPP very quickly. > > -Roman > > > > -- > > http://www.piclist.com hint: The PICList is archived three different > > ways. See http://www.piclist.com/#archives for details. > > > > > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > > > --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.237 / Virus Database: 115 - Release Date: 7/03/2001 -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.