__config 3f79

; Program RecPIC
;
; This program uses the Analogue to Digital Convertor to generate
; 8000, 8 bit samples per second. It sends these via a 115,200bps
; serial port link to a PC. The companion program "RecPIC.exe" will
; convert these samples to a ".au" file. This file can then be played
; via Windows Media Player.
;
; The PIC used is a 16F73.
; Loop length for 8000 samples/sec (125uS) and 20MHz Xtal 
; (0.2uS per instruction) is 625 Instructions
;

;Internal File Assignments
STATUS	EQU	0x03	;Used for Zero bit
PORTA	EQU	0x05
PORTB	EQU	0x06
PORTC	EQU	0x07
TXSTA	EQU	0x18
SPBRG	EQU	0x19
RCSTA	EQU	0x18
TXREG	EQU	0x19
ADRES	EQU	0x1E
ADCON	EQU	0x1F

;Internal Bit Assignments
W	EQU	0
F	EQU	1
GO	EQU	2
ZERO	EQU	2

;User File Assignments
TIMER1	EQU	0x21
COUNT	EQU	0x22
TEMP	EQU	0x23


;User Bit Assignments
GREEN     EQU      2
RED       EQU      3

;Program Starts Here!!!!!!!!!
         ORG	0x10

;Initialise Registers
	BSF 	3, 5
	BCF	3, 6
	MOVLW	0xC0
	MOVWF	PORTC    	     ;PORTC = Output except UART
	CLRF	PORTB   	     ;PORTB = Output
	MOVLW	0xFF
	MOVWF	PORTA   	     ;PORTA = Input

	MOVLW	0x0A
	MOVWF	SPBRG   	     ;Set Baud Rate to 115200
	BSF	TXSTA, 2	     ;Set Baud Rate to High
	BCF	TXSTA, 4	     ;Set Async operation
	BCF	3, 5
	BSF	RCSTA, 7
	BSF	3, 5
	BSF	TXSTA, 5

	MOVLW	0x04
	MOVWF	ADCON
	BCF	3, 5
	MOVLW	0x80
	MOVWF	ADCON
	BSF	ADCON, 0
	
	CLRF	COUNT

;Time Loop (625 instructions total)
LOOP      MOVLW 	0x10
	MOVWF	TIMER1
T0	DECFSZ	TIMER1, F
	GOTO	T0


	BSF   	ADCON, GO       
	NOP   	        	      ;Trimmer NOPs
	NOP
	NOP
	NOP
	NOP
	NOP
	NOP
	NOP
	MOVLW	0x0C
	MOVWF	PORTC
	
          MOVLW	0xBB	      ;BC+10=CC = 201*3 = 603+22=625
	MOVWF	TIMER1
T1	DECFSZ	TIMER1, F
	GOTO	T1
	MOVF	ADRES, W
	MOVWF	TXREG
	
	IORLW	0x0F
	ADDLW	0x01
	BTFSC	STATUS, ZERO
	BCF	PORTC, RED
	ADDLW	0x10
	BTFSC	STATUS, ZERO
	BCF	PORTC, GREEN
	
	GOTO	LOOP
	
	END