Old analog guy needs help with PIC16F57

**Bruce** · - 2nd March 2009, 15:05

Are you disconnecting the programmer after programming, and running the PIC on its own power supply?

You should also have a separate power supply for the PIC during ICSP. I.E. not trying to power it directly from the programmer.

If you are, then try this.

1. Program the part with your original .hex file.
2. Read it back with your programmer, and save the .hex file with another name.
3. Now open the new .hex file you just saved, and click the C box on the right.

Does it show the correct config settings?

**yankee** · - 2nd March 2009, 15:11

I'm not using ICSP. I made up an adapter cable to go directly from the programmer to the IC on a bread board.

I'm then disconnecting the program cable and testing the IC with an external power supply.

**Bruce** · - 2nd March 2009, 15:20

Have you tried the read-back yet?

**yankee** · - 2nd March 2009, 15:34

Yes, same exact results as above.

**Bruce** · - 2nd March 2009, 15:36

Strange. I would try another resonator or crystal.

**yankee** · - 2nd March 2009, 15:46

What code did you use?

**Bruce** · - 2nd March 2009, 16:13

Code:

@ device  pic16F57, hs_osc, wdt_off, protect_off

DEFINE OSC 20

Time VAR BYTE

TRISB = 0  ' all outputs
Time = 10

Main:
    PORTB = 0
    PAUSE Time
    PORTB = 255
    PAUSE Time
    Time=Time+10
    IF Time >= 250 THEN Time = 10
    GOTO Main
    
    END

Source and .hex attached.

Note: You can't disable /MCLR on this one, so make sure you have the external pull-up.