keep all assembly examples under a/assembly_*.asm

This commit is contained in:
Shark
2016-09-21 13:02:44 +02:00
parent 3bab02464b
commit 259d83e19b
6 changed files with 0 additions and 0 deletions

22
a/assembler_6502.asm Normal file
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; goodbyeworld.s for C= 8-bit machines, ca65 assembler format.
; String printing limited to strings of 256 characters or less.
a_cr = $0d ; Carriage return.
bsout = $ffd2 ; KERNAL ROM, output a character to current device.
.code
ldx #0 ; Starting index 0 in X register.
printnext:
lda text,x ; Get character from string.
beq done ; If we read a 0 we're done.
jsr bsout ; Output character.
inx ; Increment index to next character.
bne printnext ; Repeat if index doesn't overflow to 0.
done:
rts ; Return from subroutine.
.rodata
text:
.byte "Hello world!", a_cr, 0