.include "c64-1.oph"
.data
.org $C000
.space cache 2
.text
.macro print
lda #<_1
ldx #>_1
jsr printstr
.macend
.macro greet
lda #30
jsr delay
`print hello1
`print _1
`print hello2
.macend
; Save the zero page locations that PRINTSTR uses.
lda $10
sta cache
lda $11
sta cache+1
lda #147
jsr chrout
`greet target1
`greet target2
`greet target3
`greet target4
`greet target5
`greet target6
`greet target7
`greet target8
`greet target9
`greet target10
; Restore the zero page values printstr uses.
lda cache
sta $10
lda cache+1
sta $11
rts
hello1: .byte "HELLO, ",0
hello2: .byte "!", 13, 0
target1: .byte "PROGRAMMER", 0
target2: .byte "ROOM", 0
target3: .byte "BUILDING", 0
target4: .byte "NEIGHBORHOOD", 0
target5: .byte "CITY", 0
target6: .byte "NATION", 0
target7: .byte "WORLD", 0
target8: .byte "SOLAR SYSTEM", 0
target9: .byte "GALAXY", 0
target10: .byte "UNIVERSE", 0
; DELAY routine. Takes values from the Accumulator and pauses
; for that many jiffies (1/60th of a second).
.scope
.data
.space _tmp 1
.space _target 1
.text
delay: sta _tmp ; save argument (rdtim destroys it)
jsr rdtim
clc
adc _tmp ; add current time to get target
sta _target
* jsr rdtim
cmp _target
bmi - ; Buzz until target reached
rts
.scend
; PRINTSTR routine. Accumulator stores the low byte of the address,
; X register stores the high byte. Destroys the values of $10 and
; $11.
.scope
printstr:
sta $10
stx $11
ldy #$00
_lp: lda ($10),y
beq _done
jsr chrout
iny
bne _lp
_done: rts
.scend
.checkpc $A000
.data
.checkpc $D000 |