Posted by ward...@ife.ee.ethz.ch March 2, 2007
Hello all,

I\'ve spent several days now stuggling with the my PIC16F876 setup and the Wisp628 programmer. I managed to program the device once (code shown bellow) but after that found it impossible to connect again to the target (either to identify, clear, read or write).

In trying to get it going again I\'ve tried the following (unsuccessfully):
-separate power supplies for Wisp628 and PIC
-overriding the 47R /MCLR series resistor on Wisp628

Might it be that my first attempt to program (the successful one) actually used the low voltage programming and now that my code switched that off programming naturally fails. Or is part of the problem that my program drives all of PortB as an output (high).

Still both of these would not seem to account for the failure of the Wisp628 programming. The 13V on /MCLR - which looks okay - surely should override anything already on the device.

None of the related issues (that I found) on this site seem to help, but I hope someone might know what I\'m doing wrong...

Thanks in advance!
Jamie
C Code (for IAR compiler):

void main(void){

HS OSC, WDT OFF, LVP OFF
set_configuration_word( 0x3FFE & 0x3FFB & 0x3F7F )
OPTION = 0x48
option();

TRISB=0x00;
PORTB=0xFF;

while(1){
no_operation();
};
}
Wearable Computing Lab
ETH Zurich