2018-02-23 16:20:31 +00:00
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;;;
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; print_string
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; ------------
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; Print a string from memory.
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;
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; Parameters:
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; - bx: pointer to string
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;
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; Internal Variables:
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; - ah: scrolling teletype BIOS routine code
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; - al: Byte containing character to print
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; - bx: shifting pointer to string
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print_string:
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pusha ; save the state of all registers to the stack
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mov ah, 0x0e ; scrolling teletype BIOS routine code
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print_string_start:
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mov al, [bx] ; load first letter into `al'
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cmp al, 0
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je print_string_end ; if null-termination then return
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int 0x10 ; print the letter
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add bx, 0x1 ; offset to next character
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jmp print_string_start ; go back to beginning
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print_string_end:
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2018-02-23 16:38:30 +00:00
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mov al, 0xA
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int 0x10
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mov al, 0xD
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int 0x10
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2018-02-23 16:20:31 +00:00
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popa ; return the state of all the registers
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ret
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