AS09 Assembler for M6809 [1.42].                                     Page    1
--------------------------------- demo1.a09 ----------------------------------

77 lines read, no errors in pass 1.
                        *** name 'demo1.txt - a simple demonstration of 6809+a
                         title '(c) 1981, conejo computer products'
                        
                         page
AS09 Assembler for M6809 [1.42].                                     Page    2
--------------------- (c) 1981, conejo computer products ---------------------

                        
                        * file=demo1.txt
                        * 6809 / apple demo prog
                        * runs a counter on top line
                        *** opt num
1000 =                   org 4096 ; <<< change as desired <<<
07f0 =                  screen equ $7f0 ; crt address
c030 =                  beep equ $c030 ; i/o for speaker
1000 : 2002             start bra begin
1002 : 0628             adr fdb $628 ; screen addr
                        
1004 : 328d016a         begin leas endp+232,pc ; set stack pointer
1008 : ae8cf7            ldx adr,pc ; screen address
100b : 318d0065          leay msg1,pc ; "6809 COUNTING ...."
100f : a6a0             l100 lda ,y+
1011 : a780              sta ,x+
1013 : 26fa              bne l100
                        
1015 : c630             l200 ldb #'0' ; ASCII ZERO
1017 : 318d0067          leay msg1a,pc ; buffer address
101b : 6c26              inc 6,y ; from here we increment bcd digits
101d : a626              lda 6,y ; by adding 1 til '9' then do carry
101f : 8139              cmpa #'9'
1021 : 2341              bls l300
1023 : e726              stb 6,y
1025 : 6c25              inc 5,y
1027 : a625              lda 5,y
1029 : 8139              cmpa #'9'
102b : 2337              bls l300
102d : e725              stb 5,y
102f : 6c24              inc 4,y
1031 : a624              lda 4,y
1033 : 8139              cmpa #'9'
1035 : 232d              bls l300
1037 : e724              stb 4,y
1039 : 7dc030            tst beep ; click speaker
103c : 6c23              inc 3,y
103e : a623              lda 3,y
1040 : 8139              cmpa #'9'
1042 : 2320              bls l300
1044 : e723              stb 3,y
1046 : 6c22              inc 2,y
1048 : a622              lda 2,y
104a : 8139              cmpa #'9'
104c : 2316              bls l300
104e : e722              stb 2,y
1050 : 6c21              inc 1,y
1052 : a621              lda 1,y
1054 : 8139              cmpa #'9'
                        * inc a
                        ;start lda *
                        ; bra start
1056 : 230c              bls l300
1058 : e721              stb 1,y
105a : 6ca4              inc ,y
105c : a6a4              lda ,y
105e : 8139              cmpa #'9'
1060 : 2302              bls l300
1062 : e7a4              stb ,y
                        
1064 : 308d000c         l300 leax msg1,pc ; send data to crt
1068 : 10ae8c96          ldy adr,pc
AS09 Assembler for M6809 [1.42].                                     Page    3
--------------------- (c) 1981, conejo computer products ---------------------

106c : a680             l400 lda ,x+ ; move local to crt memory
106e : a7a0              sta ,y+
1070 : 26fa              bne l400
1072 : 20a1              bra l200 ; main loop
                        
1074 : 3638303920434f.. msg1 fcc "6809 COUNTING "
1082 : 3030303030303000 msg1a db "0000000",0
000e =                  cnt equ msg1a-msg1
108a =                  endp equ *
                        
108a =                   end start
                        
No errors in pass 2.
Wrote binary from address $1000 through $1089.
Total size 138 bytes.
Program start address is at $1000 (4096).