50 lines
582 B
Plaintext
50 lines
582 B
Plaintext
;Converts a byte in AL to a hex string at DI.
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byte2hex:
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;Store the initial registers in the stack
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push si
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push ax
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push bx
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push cx
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;Move the byte to AH
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mov ah, al
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;Set a key for the hex digits
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mov si, .key
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;Set a counter for the two hex digits
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mov cx, 0x2
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.loop:
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;Read a nibble
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rol ax, 0x1
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rol ax, 0x1
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rol ax, 0x1
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rol ax, 0x1
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mov bx, ax
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;Convert the nibble to a hex digit
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and bx, 0xf
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mov bl, [si + bx]
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;Store the hex digit
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mov [di], bl
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;Repeat
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inc di
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dec cx
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jnz .loop
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;Load the initial registers from the stack
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pop cx
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pop bx
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pop ax
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pop si
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ret
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.key db "0123456789abcdef"
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