******** ACIA INTERFACE ********

********************************
********************************
*D0 - Loop Counter
*D1 - DELAY LOOP COUNTER
*D2 - DISPLAY FLAG
*	$0000 = RAW DATA
*	$0001 = VOLTAGE
*D3 - DATA COUNTER (0 - 255)
*D4 - KEYSTROKE INPUT
*D5 - OUTPUT CHARACTER
*D6 - VOLTAGE REGISTER
*A3 - LABLE POINTER
*A7 - STACK POINTER
********************************
********************************


CALL	MACRO			*TRAP 14 MACRO
	MOVE.B #\1,D7
	TRAP #14
	ENDM

MAIN	EQU $1000
DATA	EQU $4000

	ORG DATA		*SET VARIABLES
RAWD	DC.B 'RAW A/D Output =    '
VOLT	DC.B 'A/D VOLTAGE    =    '
DOUT	DS.B 5


ACIAC	EQU	$10040		*ADDRESS OF CONTROL/STATUS REGISTER
ACIAD	EQU	ACIAC+2		*ADDRESS OF DATA REGISTER
RDRF	EQU	0		*RECEIVER DATA REGISTER FULL
TDRE	EQU	1		*TRANSMITTER DATA REGISTER EMPTY





********************************
***********   MAIN   ***********
********************************

	ORG MAIN
	LEA.L $7000,A7	


********** INITIALIZE **********

	MOVE.L #$0000,D1	*SET DELAY LOOP COUNTER
	MOVE.L #$0001,D2	*SET FLAG TO RAW DATA
	MOVE.L #$0000,D3	*SET DATA COUNTER
	MOVE.L #$0000,D4	*CLEAR KEYSTROKE INPUT
	MOVE.L #$0000,D5	*CLEAR OUTPUT CHARACTER	
	MOVE.L #$0000,D6	*CLEAR VOLTAGE REGISTER

	MOVE.B #$03,ACIAC	*RESET THE ACIA
	MOVE.B #$15,ACIAC 	*SETUP--DISABLE INTERRUPTS-NO PARITY
	
	MOVE.B #$0D,D5		*START NEW LINE
	BSR OUTPUT

	MOVE.B #$00,D0		*CLEAR LOOP COUNTER
	MOVE.B #$20,D5		*SPACE(ASCII$20)
CLR	BSR OUTPUT		*DISPLAY SPACE
	ADDI.B #$01,D0		*INCREMENT LOOP COUNTER
	CMPI.B #$30,D0		*20 TIMES
	BNE CLR

	MOVE.B #$0D,D5		*START NEW LINE
	BSR OUTPUT

	MOVE.B #$01,D0		*INITIALIZE LOOP COUNTER 			
	LEA.L RAWD,A3		*MOVE ADDRESS OF LABLE TO A3
LPI	MOVE.B (A3)+,D5		*MOVE CHARACTER FOR LABLE TO D5
	BSR OUTPUT	
	ADDI.B #$01,D0		*INCREMENT LOOP COUNTER			
	CMPI.B #$14,D0		*COMPLETE LOOP 20 TIMES
	BNE LPI	

	BRA NOINC		*GOTO INITIAL DATA DISPLAY W/O INC

********************************

LOOP	ADD.L #$0001,D3		*INCREMENT COUNTER
	CMPI.W #$100,D3		*COMPARE COUNTER VALUE TO &256
	BNE NOINC
	MOVE.L #$0000,D3	*COUNTER = 256 RESET

NOINC	BSR DELAY		*0.2 SEC DELAY
	BSR DISDAT		*DISPLAY DATA

	BTST.B #RDRF,ACIAC	*TEST RECEIVER STATUS
	BNE GETCH		
	BRA LOOP		*NO KEYSTOKE BRA TO LOOP




********************************
********* SUBROUTINES **********
********************************

************* DELAY ************

DELAY	MOVE.L #$AFFF,D1
DLOOP	SUBI.L #$1,D1
	BNE DLOOP		*DELAY FOR 0.2 SEC
*	MOVE.L #$FFFF,D1
*DLP	SUBI.L #$1,D1
*	BNE DLP	

	RTS


********** GET KEYSTOKE ********

GETCH	MOVE.B ACIAD,D4
	ANDI.B #$DF,D4		*CONVERT TO ALL CAPS
	BSR TCHAR		*TEST CHAR
	BRA LOOP


********** DISPLAY DATA ********

DISDAT	MOVE.B #$08,D5		*BACKSPACE*3 (ASCII$08)
	BSR OUTPUT
	BSR OUTPUT
	BSR OUTPUT
	
	CMPI.B #$01,D2		*CHECK DISPLAY FLAG
	BEQ VT


	MOVE.W D3,D0		*MOVE RAW DATA FOR CONVERSION
	CALL 236		*TRAP#14 HEX2DEC

	MOVE.B #$03,D0		*INITIALIZE LOOP COUNTER
DISCH	MOVE.B (A5)+,D5		*OUTPUT CHARACTER
	BSR OUTPUT
	SUBI.B #$01,D0		*DECREMENT COUNTER
	CMP.L A5,A6		*CHECK FOR END OF STRING
	BNE DISCH
	
DISSP	CMPI.B #$00,D0		*CHECK FOR END OF DISPLAY
	BEQ EX			*RETURN IF END OF DISPLAY
	MOVE.B #$20,D5		*DISPLAY SPACE(ASCII$20)
	BSR OUTPUT
	SUBI.B #$01,D0		*DECREMENT COUNTER
	BRA DISSP

EX	RTS

*	MOVE.B (A5)+,D5		*MOVE UDS OF RAW DATA TO D5
*	BSR OUTPUT		*DISPLAY RAW DATA(UDS)
*	
*	MOVE.B (A5),D5		*MOVE LDS OF RAW DATA TO D5
*	BSR OUTPUT		*DISPLAY RAW DATA(LDS)
*		
*	RTS


VT	MOVE.W D3,D6		*MOVE RAW DATA TO BE CONVERTED
        CMP.W #$32,D6
	BGT VTH

	MULU.W #$32,D6
	DIVU.W #$FF,D6
        MOVE.W D6,D0
	LEA DOUT,A5
	LEA DOUT,A6
	CALL 236

	MOVE.B #'0',D5
	BSR OUTPUT

	MOVE.B #$2E,D5
	BSR OUTPUT

	MOVE.B (A5),D5
	BSR OUTPUT

	RTS


VTH	MULU.W #$32,D6
	DIVU.W #$FF,D6
	MOVE.W D6,D0		*Move voltage for conversion for ASCII
	LEA DOUT,A5
	LEA DOUT,A6
	CALL 236		*TRAP#14 HEX2DEC

	MOVE.B (A5)+,D5
	BSR OUTPUT

	MOVE.B #$2E,D5
	BSR OUTPUT

	MOVE.B (A5),D5
	BSR OUTPUT

	RTS	



*	MULU.W #$1F4,D6
*	BRA VD
*
*VTT	MULU.W #$32,D6
*
*VD	DIVU.W #$FF,D6
*
*	MULU.W #$32,D6		*CONVERT RAW DATA TO VOLAGE
*	DIVU.W #$FF,D6
*
*				
*	MOVE.W D6,D0		*MOVE VOLTAGE FOR CONVERSION 
*	CALL 236		*TRAP#14 HEX2DEC
*
*
*VTZ	MOVE.B #'0',D5		
*	BSR OUTPUT		
*	
*	MOVE.B #$2E,D5		*DISPLAY '.'
*	BSR OUTPUT
*
*	MOVE.B #'0',D5			
*	BSR OUTPUT		
*	
*	RTS
				

******* OUTPUT TO CRT **********

OUTPUT	BTST.B #TDRE,ACIAC	*TEST TRANSMITTER STATUS
	BEQ OUTPUT		*POLL UNTIL TRANSMITTER READY FOR DATA
	MOVE.B D5,ACIAD		*TRANSMIT THE DATA
	RTS


********** TEST CHAR ***********

TCHAR	CMPI.B #'V',D4		*CHAR = 'V'?
	BNE RD
	MOVE.L #$0001,D2	*DISPLAY FLAG =1

	MOVE.B #$0D,D5		*MOVE TO BEGINNING OF LINE
        BSR OUTPUT

	MOVE.B #$01,D0		*INITIALIZE LOOP COUNTER 			
	LEA.L VOLT,A3		*MOVE ADDRESS OF LABLE TO A3
LPV	MOVE.B (A3)+,D5		*MOVE CHARACTER FOR LABLE TO D5
	BSR OUTPUT	
	ADDI.B #$01,D0		*INCREMENT LOOP COUNTER
	CMPI.B #$14,D0		*COMPLETE LOOP 20 TIMES
	BNE LPV	

	BSR DISDAT
	RTS

RD	CMPI.B #'R',D4		*CHAR = 'R'?
	BNE CC
	MOVE.L #$0000,D2	*DISPLAY FLAG = 0
	
	MOVE.B #$0D,D5		*MOVE TO BEGINNING OF LINE
	BSR OUTPUT

	MOVE.B #$01,D0		*INITIALIZE LOOP COUNTER 			
	LEA.L RAWD,A3		*MOVE ADDRESS OF LABLE TO A3
LPR	MOVE.B (A3)+,D5		*MOVE CHARACTER FOR LABLE TO D5
	BSR OUTPUT	
	ADDI.B #$01,D0		*INCREMENT LOOP COUNTER
	CMPI.B #$14,D0		*COMPLETE LOOP 20 TIMES
	BNE LPR

	BSR DISDAT
	RTS

CC	CMPI.B #'C',D4		*CHAR = 'C'?
	BNE TR
	BSR CLRCNT
	RTS

TR	CMPI.B #'Q',D4		*CHAR = 'Q'?
	BNE IK
	BSR TUTOR

IK	BRA LOOP		*INVALID KEYSTROKE


	

********** CLEAR COUNTER *******

CLRCNT	MOVE.L	#$0000,D3	*RESET COUNTER
	BRA NOINC


********** RETURN TO TUTOR *****

TUTOR	CALL 228		*RETURN TO TUTOR	

	END