PIC16F876A IDC Run time interrupt

[clem]

I'm using a melabs U2/USB Programmer w/ Microcode studio plus - PICBASIC PRO.
I've followed the instructions for physical connections and precautions on the MELabs website entitled "In-Circuit Serial Programming (ICSP) with the EPIC™ Programmer, melabs Serial Programmer, or melabs U2/USB Programmer"
When I perform a standard compile and program the PIC works great, when I try an ICD compile and program it appears to complete but when I try to run the program I get an ICD connection timeout.
I tried the Oscillator Setting, the Disable Debug Directive, the Define loader and physically resetting the PIC at the MCLR pin.
What could possibly be the issue?

[Darrel Taylor]

Are you using any HSER DEFINE's ?

If so, comment them out.
MCSP sets the baud rate for the USART while debugging
<br>

[clem]

PULSE VAR PORTC.2
RL1 VAR PORTC.1
RL2 VAR PORTC.0
HEATIN VAR PORTA.1
SENSIN VAR PORTA.0
ADCON1 = 0011 'Declare A ports 0 & 1 as Analog to dig converters
ADCON1.7 = 1 'Analog to Digital variables declared right justified
TRISA = 255
DEFINE ADC_BITS 10 '10 bit conversion used
DEFINE ADC_SAMPLEUS 5 'set sample time
SENSVAL VAR Byte
DEFINE LOADER_USED 1
DISABLE DEBUG


loop_delay CON 500 ' adjust to tweak timing
ms_count VAR WORD


loop:

FOR ms_count = 0 TO 999 ' 0 to 999mS

IF ms_count < 14 THEN ' PULSE low 0 to 13 mS
low PULSE
ELSE ' PULSE and RL1 high at 14
high PULSE
high RL1
high RL2
ENDIF

IF MS_count > 8 THEN ' RL1 low at 9 mS
high RL2
ENDIF

IF ms_count > 995 THEN ' RL2 low at 995 mS, high at 0
low RL1
ENDIF

IF ms_count = 997 THEN ' Read PORTA.0 ADC VALUE put in mem loc 0
ADCIN PORTA.0, SENSVAL
ENDIF

IF ms_count < 500 THEN
High 0
ENDIF

IF ms_count > 499 THEN
low 0
ENDIF

IF ms_count < 500 THEN
low 1
ENDIF

IF ms_count > 499 THEN
high 1
ENDIF

PAUSEUS loop_delay ' fill in time for 1mS loop

NEXT ms_count

goto loop
END

[Darrel Taylor]

Are you using a MAX232 between the USART and the PC.

Or, are you trying to use the melabs U2 to debug. (won't work)

Also, 99% of your program is disabled. Remove the DISABLE DEBUG.
<br>

[clem]

I am not using the MAX 232...
I take it is a must!?

[mister_e]

I am not using the MAX 232...
I take it is a must!?

Yes Indeed, look the Help file... under the Hardware requirement. You'll discover something interesting

tutorial
http://www.rentron.com/PicBasic/MCS_X3.htm

schematic

[Darrel Taylor]

I am not using the MAX 232...
I take it is a must!?

Yes, it's a MUST.

Microcode Studio's ICD communicates with the PIC via the RS232 port, and uses the USART on the PIC.
There's no other way to do it.
<br>

[mister_e]

And i think it's not the whole thing as well... some variable declaration are missing... AND...

ADCON1 = 0011 'Declare A ports 0 & 1 as Analog to dig converters

unless there's a copy/paste error here, it may screw few things... No i didn't open TFM to know how much ADCON=11 is different of ADCON1=%0011