94 lines
1.6 KiB
ArmAsm
94 lines
1.6 KiB
ArmAsm
.forceimport __STARTUP__
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.export _main
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.segment "RODATA"
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; All numbers are going to be this size and type.
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Unsigned_Integer_Size = 4
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; Standard character output routine
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COUT = $fded
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.segment "BSS"
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Sleep_Loop_Count: .res Unsigned_Integer_Size,0 ; Byte values initialized to 0
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; *************************************
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;
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; Macros
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;
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; *************************************
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; Number++
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.macro Increment Number
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.local Next_Byte
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.local Done
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ldx #0 ; X := 0
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Next_Byte:
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inc Number,X ; Increment the value at Count+X address
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bne Done ; Incrementing Count did not cause it to roll over to 0.
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inx ; Increment X to the next byte
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cpx #Unsigned_Integer_Size ; Compare X with 4.
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bmi Next_Byte ; If X < Count_Size continue with next byte.
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Done:
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.endmacro
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; Minuend = Minuend - Subtrahend
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.macro Subtract Minuend, Subtrahend
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.local Next_Byte
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ldx #0
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clc
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Next_Byte:
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lda Addr1,X
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sbc Addr2,X
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inx
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cpx #Unsigned_Integer_Size
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bmi Next_Byte
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.endmacro
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; *************************************
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;
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; Main
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;
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; *************************************
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.segment "CODE"
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.proc _main: near
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.segment "CODE"
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Sleep_Loop:
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; Do nothing 10 times.
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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Increment Sleep_Loop_Count
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lda #1
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cmp Sleep_Loop_Count+3
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bmi Sleep_Loop
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; Output result
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ldx #0
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Next_Byte:
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lda Sleep_Loop_Count,X
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jsr COUT
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inx
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cpx #Unsigned_Integer_Size
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bmi Next_Byte
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rts ; from _main
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.endproc
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