24 lines
864 B
Text
24 lines
864 B
Text
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PrintString:
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lda (StringPtr),y
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beq Terminated
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cmp #'\' ; a single ascii character is specified in single quotes.
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beq HandleSpecialChars
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jsr PrintChar ;unimplemented print routine
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iny ;next character
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jmp PrintString ;back to top
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Terminated:
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rts ;exit
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HandleSpecialChars:
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iny ;next char
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lda (StringPtr),y
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cmp #'n'
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beq NextLine ;unimplemented new line routine, it ends in "JMP DoneSpecialChar."
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;Typically this would reset the x cursor and increment the y cursor, which are software variables that
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;get converted to a VRAM address in some other routine.
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DoneSpecialChar:
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iny
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jmp PrintString ;jump back to top. Notice that neither the backslash nor the character after it were actually printed.
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