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PIC16f877a Serial Communication problem

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FinalTrigger

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Hey guys, in class im working on a serial communication function for the pic16f877a. What i have is of course the microchip, a 10 segment LED (looks like Binary) and a photo resistor. So what im trying to do is a Analog to Digital Conversion (which i was able to complete) but now send the value that was given from the conversion (ADRESH) to an output for communication ( to myself...send and receive) and take the value from the recieve register and move it to PORTD which i have connected to my 10 segment display. I believe i have my interrupts set wrong, because i think the processor is getting stuck and not reseting / continuing. if anyone can help i would highly appreciate it.:D

Code:
 	list	p=16f877
		#include <p16f877a.inc>

			org		0x04
			goto	ISR
			org		0x000
			goto	Start

Start		org		0x020
			bsf		STATUS, 5		;select Bank 1
			bcf		STATUS, 6		
			movlw	B'10000111'		;same as 0x87
			movwf	OPTION_REG		;sets up Timer 0
			movlw	0x80
			movwf	TRISC			;sets pin 1 as input
			movlw	0x00
			movwf	TRISD
			bsf		PIE1,	4		;enable TXIE for interupts
			bsf		PIE1,	5		;enable RCIE for interupts
			bsf		PIE1,	6		;enable ADIE interupt enable bit
			bsf		TXSTA,	4		;clear SYNC for asynchronous mode
			bsf		TXSTA,	5		;enable the transmission by setting TXEN, also sets TXIF
			movlw	0x0c
			movwf	SPBRG			;sets baud rate for serial port
			movlw	B'11100000'		
			movwf	INTCON			;sets GIE and PEIE in Interupts
			movlw	0x0E
			movwf	ADCON1			;set up ADCON1 Register
			bcf		STATUS, 5		;select Bank 0
			movlw	B'00000001'		;set up the ADCON0 Register and clear Go/Done
			movwf	ADCON0
			bcf		STATUS, 6	
			bsf		RCSTA,	7		;set SPEN to enable serial ports
			bsf		RCSTA,	4		;enable CREN for reception
			clrf	PORTD
			comf	PORTD,	f
			call	LoopTimer
			clrf	PORTC
		
;''''''''''''''''''''''''''''Asynch Transmition''''''''''''''''''''''''''''''''''
		;	movlw	0x0c
		;	movwf	SPBRG			;sets baud rate or serial port
		;	bcf		TXSTA,	4		;clear SYNC for asynchronous mode
		;	bsf		RCSTA,	7		;set SPEN to enable serial ports
	;		bsf		PIE1,	4		;enable TXIE for interupts
		;	bsf		TXSTA,	5		;enable the transmission by setting TXEN, also sets TXIF
		;	movlw	B'11000000'		;sets GIE and PEIE in Interupts
		;	movwf 	INTCON
;''''''''''''''''''''''''''''Asynch Reception''''''''''''''''''''''''''''''''''''
	;		bsf		PIE1,	5		;enable RCIE for interupts
	;		bsf		RCSTA,	4		;enable CREN for reception
			
;'''''''''''''''''''''''''''''''''Main''''''''''''''''''''''''''''''''''''''''''''''
Main	;	movfw	Recieve
			movfw	Digital
			movwf	PORTD
			goto	Main
;********************************ADC*************************************************

ADC		;	movlw	B'00000001'		;set up the ADCON0 Register and clear Go/Done
		;		movwf	ADCON0
			btfsc	ADCON0,	2		;test the go/done bit in ADCON0 to see if complete
			goto	$-1				;go back 1 step to test Go/done
			movfw	ADRESH			;moves the value in ADRESH to w register
			movwf	Digital			;moves the value from w register to Digital Register
			bsf		ADCON0, 2		;set the Go/Done bit in ADCON0
			bcf		PIR1,	6		;clear bit 6 to notify A/D Convertion not complete
			return
;''''''''''''''''''''''''''''''''Transmition''''''''''''''''''''''''''''''''''''''''
Transmition	movfw	Digital
			movwf	TXREG			;moves digital value to TXREG
			bsf		PIR1,	4
			return
;'''''''''''''''''''''''''''''''''Reception'''''''''''''''''''''''''''''''''''''''''
Reception	movfw	RCREG
			movwf	Recieve			;moves Recieving data to Recieve Register to save data
			bsf		PIR1,	5
			return
;*******************************Loop Timer*******************************************
LoopTimer	btfss	INTCON, 2		;test for overflow of timer
			goto	LoopTimer		;loop back until overflow happens
			bcf		INTCON, 2		;reset timer overflow bit
			return
;'''''''''''''''''''''''''''''''Interupt Service Routine'''''''''''''''''''''''''''''
ISR			btfsc	PIR1,	6		;tests ADIF
			call	ADC
			btfsc	PIR1,	4		;tests TXIF
			call	Transmition
			btfsc	PIR1,	5		;tests RCIF
			call	Reception
			btfsc	INTCON,	2	
			call	LoopTimer		
			retfie
;*****************************Registers***********************************************
Digital		equ		0x35			;assign register 0x35 to Digital
Recieve		equ		0x36			;assign register 0x36 to Recieve
			end
 
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