ca65 V2.17 - Git 582aa41
Main file   : tape_programs.ca65
Current file: tape_programs.ca65

000000r 1               ;
000000r 1               ; ACORN System 1 Applications: Tape Use Programs
000000r 1               ;
000000r 1               ; From the Acorn System 1 User's Manual
000000r 1               ;
000000r 1               ; (Chris Oddy January 2022)
000000r 1               ;
000000r 1               ; entry points Test: $0200, Retag: $0208
000000r 1               ;
000000r 1               		.setcpu			"6502"
000000r 1               		.listbytes		unlimited
000000r 1               ;
000000r 1               D		:=		$10
000000r 1               QDATFET	:=		$FE88		; quad data fetch
000000r 1               COM16	:=		$FEA0		; compare 16-bit numbers
000000r 1               PUTBYTE	:=		$FEB1		; put byte to tape
000000r 1               RESTART	:=		$FF04		; Monitor reentry point
000000r 1               ;
000000r 1               		.org			$0200
000200  1               ;
000200  1  A9 55        TEST:	lda		#$55		; the test byte
000202  1  20 B1 FE     		jsr		PUTBYTE		; send it
000205  1  4C 00 02     		jmp		TEST		; keep sending it
000208  1               ;
000208  1  A9 F1        RETAG:	lda		#$F1		; F. prompt
00020A  1  85 10        		sta		D
00020C  1  A2 06        		ldx		#$06
00020E  1  20 88 FE     		jsr		QDATFET		; first address
000211  1  A2 08        		ldx		#$08
000213  1  86 10        		stx		D			; prompt
000215  1  20 88 FE     		jsr		QDATFET		; second address
000218  1  A9 46        		lda		#$46		; prompt
00021A  1  85 10        		sta		D
00021C  1  A2 20        		ldx		#$20
00021E  1  20 88 FE     		jsr		QDATFET		; last address: actual data start
000221  1  A2 04        		ldx		#$04
000223  1  B5 05        ADRSS:	lda		$05,x		; send fake address
000225  1  20 B1 FE     		jsr		PUTBYTE
000228  1  CA           		dex
000229  1  D0 F8        		bne		ADRSS
00022B  1  A0 00        DATAS1:	ldy		#$00
00022D  1  B1 20        		lda		($20),y		; proper data
00022F  1  E6 20        		inc		$20			; increment proper data counter
000231  1  D0 02        		bne		NOINC
000233  1  E6 21        		inc		$21
000235  1  20 B1 FE     NOINC:	jsr		PUTBYTE		; send data
000238  1  20 A0 FE     		jsr		COM16		; check fake addresses for end
00023B  1  D0 EE        		bne		DATAS1
00023D  1  4C 04 FF     		jmp		RESTART
00023D  1