C64 - Move the cursor using the arrow keys

C64ArrowCursor.asm

;*********************************************
;* Arrow Cursor, W,S,A,D		     *
;*********************************************

		processor 6502
		org $1000

;setup helpful labels
CLEAR 	= $E544
CHROUT 	= $FFD2
GETIN  =  $FFE4
SCNKEY =  $FF9F 

ENTER	= $C202
INVERSE = $C204
NORMAL 	= $C206
MARK 	= $C208

		JSR CLEAR
		
		LDA	#13
		STA $C202
		
		LDA #32
		STA MARK
		
		LDA #18
		STA INVERSE
		
		LDA #146
		STA NORMAL
		
		LDA #0
		
SCAN	        JSR SCNKEY	;get key
		JSR GETIN	;put key in A

START	        CMP #87		;W - up
		BEQ UP
		
		CMP #83		;S - down
		BEQ DOWN
		
		CMP #65		;A - left
		BEQ LEFT
		
		CMP #68		;D - right
		BEQ RIGHT
		
		CMP ENTER	;end if enter clicked
		BEQ END
		
CURSOR	LDA	MARK	
		JSR CHROUT
		
		LDA #157
		JSR CHROUT
		
		LDA NORMAL
		JSR CHROUT
		
		LDA MARK
		JSR CHROUT
		
		LDA #157
		JSR CHROUT
		
		LDA INVERSE
		JSR CHROUT
		
		JMP SCAN
		
UP		LDA #145
		JMP PRINT
		
DOWN	        LDA	#17
		JMP PRINT

LEFT	        LDA #157
		JMP PRINT

RIGHT	        LDA	#29
		JMP PRINT

PRINT	        JSR CHROUT
		JMP CURSOR

END		RTS