mirror of
https://github.com/cfenollosa/os-tutorial.git
synced 2024-09-29 23:10:50 +00:00
38 lines
594 B
NASM
38 lines
594 B
NASM
print:
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pusha
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; keep this in mind:
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; while (string[i] != 0) { print string[i]; i++ }
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; the comparison for string end (null byte)
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start:
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mov al, [bx] ; 'bx' is the base address for the string
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cmp al, 0
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je done
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; the part where we print with the BIOS help
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mov ah, 0x0e
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int 0x10 ; 'al' already contains the char
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; increment pointer and do next loop
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add bx, 1
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jmp start
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done:
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popa
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ret
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print_nl:
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pusha
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mov ah, 0x0e
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mov al, 0x0a ; newline char
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int 0x10
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mov al, 0x0d ; carriage return
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int 0x10
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popa
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ret
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