TEST 6502

(Updated November 18, 2024)

define CHROUT $ffd2

    ldx #0        ; set index to zero
print:
    lda words,x   ; load a letter from words
    beq done      ; if it's the zero, we're done
    jsr CHROUT    ; print the character
    inx           ; increment the index
    bne print     ; keep printing
done:
    brk           ; end!

; data below this line

words:
    txt "The quick brown\nfox jumps over\n"
    txt "the lazy dog.\n"
    dcb 0

         *= $4000    ; start at address $4000

define linprt $bdcd
define chrout $ffd2

         ldx num1
         lda num1+1
         jsr printxa
         ldx num2
         lda num2+1
         jsr printxa

adding:  clc
         lda num2
         adc num1
         sta sum
         lda num2+1
         adc num1+1
         sta sum+1

         ; this is printing the sum
prtsum:  ldx sum
         lda sum+1
printxa: jsr linprt

         lda #13
         jmp chrout  ; rts from call

         rts

num1:    dcw 3650
num2:    dcw 1217
sum:     dcw 0