mirror of
https://github.com/fumiama/c64-snake.git
synced 2026-06-05 16:50:28 +08:00
33 lines
577 B
NASM
33 lines
577 B
NASM
.outfile "printinput.prg"
|
||
.require "platform/c64header.oph"
|
||
.require "platform/c64kernal.oph"
|
||
|
||
.data
|
||
.org $C000
|
||
.space _na 1 ; a的临时存放处
|
||
|
||
.text
|
||
main:
|
||
* jsr getin
|
||
beq skip
|
||
jsr printbyte
|
||
lda #13 ; 换行
|
||
jsr chrout
|
||
skip:
|
||
jmp -
|
||
|
||
printbyte:
|
||
sta _na
|
||
txa
|
||
pha
|
||
ldx #7 ; 打印8bit
|
||
* lda #$30 ; a = '0'
|
||
asl _na ; 左移一位，溢出到c
|
||
bcc + ; if(c == 0) goto 下一个星号
|
||
adc #0 ; else a = a + c + 0
|
||
* jsr chrout ; putchar(a)
|
||
dex ; x--
|
||
bne -- ; if(x != 0) goto 上两个星号
|
||
pla
|
||
tax
|
||
rts |