I have successfully written and debugged my first project on an 16F877 using
the ICD. (With a good deal of help from the archives...thanks!). I have
ported the code to the 16F628 for my final implementation, but with no joy -
I get no output on any pins - my logic probe indicates the portA pins are
floating (hence not set for output). I am setting the CMCON bits (0x07) and
resetting the TRISA bits.

In total desparation, I changed the program to just a simple led blinking
app, with the same results...works on the '877 but no go on the '628. If I
step through it with the simulator, it works fine.

I am using Myke Predko's "El Cheapo" programmer and it reports that the part
programmed OK (and the verify function confirms). If I remove the part from
the programmer I get errors, so I assume the programmer at least "thinks"
everything is OK. I even tried tying pin10 to ground as has been discussed
here. One concern I have is that it only takes a second or so to program (my
program is 496 words). Is this a reasonable time to download this program?
It is significantly faster than the MPLAB/ICD, which takes a few seconds.

I have to assume it's something stupid I'm doing, but I've spent hours
trying to debug this problem. I checked the .lst file and the fuse bits all
look correct, as does the conditional code.

Any assistance would be greatly appreciated; I am at my wits' end.

Here is the guts of my (simple test) code...

.
.
.
IntsOff Macro
  clrf  INTCON
 EndM

IntsOn Macro
  movlw  (1 << GIE) | (1 << T0IE)
  movwf  INTCON
 EndM

 ifdef __16F877
#define SegPort PORTD
#define TRISSegPort TRISD
 endif
 ifdef __16F628
#define SegPort PORTB
#define TRISSegPort TRISB
 endif

;  Registers

 ifdef __16F877
 __CONFIG _CP_OFF & _DEBUG_OFF & _XT_OSC & _PWRTE_ON  & _WDT_OFF & _LVP_OFF
& _WRT_ENABLE_ON & _BODEN_ON & _CPD_OFF
 endif
 ifdef __16F628
 __CONFIG _CP_OFF & _XT_OSC & _PWRTE_ON  & _WDT_OFF & _LVP_OFF & _BODEN_ON &
_MCLRE_OFF
 endif

  PAGE

 org     0

  nop
  goto   Main

 org     4

Int
  bsf    TimerInt, 0
  incf   TimerCount, f
  bcf    INTCON, T0IF
  retfie

Main

 ifdef __16F628
  movlw  7
  movwf  CMCON              ;  All RA pins digital
 endif
  bsf    STATUS, RP0        ;  Goto Bank 1 to set Port Direction
  movlw  B'11000011'        ;  Timer bits, prescaler 8:1
  movwf  OPTION_REG
 ifdef __16F877
  movlw  6
  movwf  ADCON1          ;  All RA pins digital
 endif
  bcf    TRISA, 0        ;  Set RA0 to Output
  bcf    TRISA, 1        ;  Set RA1 to Output
  bcf    TRISA, 2        ;  Set RA2 to Output
  clrf   TRISSegPort     ;  Make all pins in Segport output
  bcf    STATUS, RP0     ;  Go back to Bank 0
  clrf   PA
  clrf   PORTA
  clrf   SegPort
  clrw

x                ; just flash a led on RA0
  movlw  1
  xorwf  PA, w
  movwf  PA
  movwf  PORTA
  call   DelayLong
  call   DelayLong
  call   DelayLong
  call   DelayLong
  call   DelayLong    ; total about half a second
  goto   x
  .
  .
  .


Sorry for the long post.

TIA

Gary

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