;PROGRAM ENVIRONMENT
	;RAM locations used for the program 	9000-9FFF
	STACK .EQU 91FFH	;Stack pointer initialised at 91FF
	PORTA .EQU 08H 		;PORT A of 8255
	PORTB .EQU 09H 		;PORT B of 8255
	PORTC .EQU 0AH 		;PORT C of 8255
	CWR(8255) .EQU 0BH 	;Control Word of 8255 
	CWR(8279) .EQU 01H 	;Control Word of 8279
	DAT(8279) .EQU 00H 	;Data Address of 8279
	RDKBD .EQU 0A64H	;Location of KIT keyboard subroutine
	CLEAR .EQU 0B00H	;Location of display Clear subroutine
       .ORG 9000H
	LXI SP,STACK 
	MVI A ,80H 		;8255 Control word for Ports A,B and C as output
	OUT CWR(8255)		;
LOOP:	CALL MESSAGE   		;Call subroutine for message display
	CALL RDKBD		;An utility subroutine in the kit to Accept hex digit  form the keyboard 
	CPI 11H			;Compare with next key code
	JNZ LOOP
	CALL CLEAR		;Clear display
CHECK:	CALL RDKBD   
	ANI 0FH			
	CPI 01H
	JZ P1
	CPI 02H
	JZ P2
	CPI 03H
	JZ P3
	CPI 04H
	JZ P4
	CPI 05H
	JZ P5
	JMP CHECK
	HLT
P1:	CALL CLEAR		;Pattern1 subroutine
	MVI A,20H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A,06H		;7-SEGMENT CODE FOR '1'
	OUT DAT(8279)		;Display acc content 
	MVI A,73H		;7 SEGMENT CODE FOR 'P'
	OUT DAT(8279)
	LXI H,PATTERN1          ;Pattern1 location 9310H
	MVI C,08H		;No. of data in pattern1
	CALL DISPLAY
	JMP P1
P2:	CALL CLEAR		;Pattern2 subroutine
	MVI A,20H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A,5BH		;7 SEGMENT CODE FOR '2'
	OUT DAT(8279)		;Display acc content 
	MVI A,73H		;7 SEGMENT CODE FOR 'P'
	OUT DAT(8279)	
	LXI H,PATTERN2		;Pattern2 location 9320H
	MVI  C,06H		;No. of data in pattern2
	CALL DISPLAY
	JMP P2
P3:	CALL CLEAR		;Pattern3 subroutine
	MVI A,20H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A,4FH		;7 SEGMENT CODE FOR '3'
	OUT DAT(8279)		;Display acc content 
	MVI A,73H		;7 SEGMENT CODE FOR 'P'
	OUT DAT(8279)	
	LXI H,PATTERN3		;Pattern3 location 9330H
	MVI C,06H 		;No. of data in pattern3
	CALL DISPLAY
	JMP P3
P4:	CALL CLEAR		;Pattern4 subroutine
	MVI A,20H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A,66H		;7 SEGMENT CODE FOR '4'
	OUT DAT(8279)		;Display acc content 
	MVI A,73H		;7 SEGMENT CODE FOR 'P'
	OUT DAT(8279)
	LXI H,PATTERN4		;Pattern4 location 9340H
	MVI  C,04H		;No. of data in pattern4
	CALL DISPLAY
	JMP P4
P5:	CALL CLEAR		;Pattern5 subroutine
	MVI A,20H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A,6DH		;7 SEGMENT CODE FOR '5'
	OUT DAT(8279)		;Display acc content 
	MVI A,73H		;7 SEGMENT CODE FOR 'P'
	OUT DAT(8279)
	LXI H,PATTERN5		;Pattern5 location 9350H
	MVI  C,08		;No. of data in pattern5
	CALL DISPLAY
	JMP P5
DISPLAY: MOV A,M 		;Display subroutine
	OUT PORTA		;acc content in port A
	OUT PORTB	    	;acc content in port B
	OUT PORTC		;acc content in port C
	CALL DELAY
	CALL DELAY
	INX H			;point to next memory location
	DCR C			
	JNZ DISPLAY
	RET
	

MESSAGE: MVI A,04H		;mode setting of 8279
	OUT CWR(8279)		;control word for 8279
	MVI A, 79H		;7 SEGMENT CODE FOR 'E'
	OUT DAT(8279)		;Display acc content 
	MVI A, 5EH		;7 SEGMENT CODE FOR 'd'
	OUT DAT(8279)		;Display acc content
	MVI A, 3FH		;7 SEGMENT CODE FOR 'O'
	OUT DAT(8279)		;Display acc content
	MVI A, 39H		;7 SEGMENT CODE FOR 'C'
	OUT DAT(8279)		;Display acc content
	RET
DELAY:	LXI D,0FFFFH		;Delay subroutine
L2:	DCX D
	MOV A,E
	ORA D
	JNZ  L2
	RET

          .ORG 9310H
PATTERN1: .DB 80H	
          .DB 50H	
          .DB 20H	
          .DB 10H	
          .DB 08H	
          .DB 05H	
          .DB 02H	
          .DB 01H	
          .ORG 9320H
PATTERN2: .DB 55H	
          .DB 0AAH	
          .DB 0CCH	
          .DB 33H	
          .DB 0F0H	
          .DB 0FH	
          .ORG 9330H
PATTERN3: .DB 81H	
          .DB 42H	
          .DB 24H	
          .DB 18H	
          .DB 24H	
          .DB 42H	
          .ORG 9340H
PATTERN4: .DB 81H	
          .DB 18H	
          .DB 42H	
          .DB 24H	
          .ORG 9350H
PATTERN5: .DB 07FH	
          .DB 0BFH	
          .DB 0DFH	
          .DB 0EFH	
          .DB 0F7H	
          .DB 0FBH	
          .DB 0FDH	
          .DB 0FEH	
          .END