At 17:20 17/03/97 -0800, you wrote:
>I'm trying to program a 16C84 with a low cost PARALLAX programmer
>and have some trouble:
>        1/ I'm obliged to program 3 or 5 times the chip to have
>the oscillator programmed for CRYSTAL and not RC
>        2/ I have the programmed chip (SMD), then sold it onto the board.
>I connect RB6,RB7, MCLR and VCC to the programmer in order to modify
>the program. Problem is as the chip is programmed for Crystal oscillator
>the programmer as many difficulties to read and program it.
>
>Does anybody know if it's necessary the oscillator section run properly
>to re-program a 16C84 ?
>Does somebody have the same problem with a parallax programmer ?

 I've tried the in-circuit programming with a DIY "LUDIPIPO" programmer,
and I've found that the extra power consummed by the PIC while it is in the
circuit (with the oscilator running) make it impossible  to re-program. May
be the Parallax Programmer works in a simmilar way (I dont'k know), then
you need a programmer with its own power supply (just what I'm trying to
build now ).

 good lucky.


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