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        LDX #$00           ; Start at the beginning of the message
        LDY #$00           ; Initialize Y register for indexing

LOOP:   LDA MESSAGE,X      ; Load the next character
        BEQ DONE           ; If zero (end of string), we're done
        JSR SEND_CHAR      ; Otherwise, send the character
        INX                ; Move to the next character
        BNE LOOP           ; Repeat until end of string

DONE:   RTS                ; Return from subroutine

SEND_CHAR:
        ; Assume the character is in A
        ; Code to send A over RS-232 goes here
        RTS                ; Return from subroutine

MESSAGE:
        .BYTE "Hello, World!", $00  ; Null-terminated string

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SORT:   
        LDY #$00           ; Outer loop index
OUTER_LOOP:
        LDX #$00           ; Inner loop index
        LDA #$00           ; Flag to check if swapped
        STA SWAPPED

INNER_LOOP:
        LDA ARRAY,X        ; Load current element
        CMP ARRAY+1,X      ; Compare with next element
        BCC NO_SWAP        ; If already sorted, skip swap

        ; Swap elements
        LDA ARRAY,X
        PHA
        LDA ARRAY+1,X
        STA ARRAY,X
        PLA
        STA ARRAY+1,X

        LDA #$01
        STA SWAPPED        ; Mark that we swapped

NO_SWAP:
        INX
        CPX #ARRAY_LENGTH-1
        BNE INNER_LOOP

        LDA SWAPPED
        BEQ DONE_SORTING

        INY
        CPY #ARRAY_LENGTH-1
        BNE OUTER_LOOP

DONE_SORTING:
        RTS

ARRAY:
        .BYTE 5, 3, 8, 4, 2, 7
ARRAY_LENGTH = 6
SWAPPED:
        .BYTE 0