Difference between revisions of "PM Opc DIV"
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; H will be the Remainder/Rest | ; H will be the Remainder/Rest | ||
− | + | Ds = HL ÷ A | |
− | H = HL % A | + | IF Ds < 256 THEN |
+ | L = Ds ; Quotient | ||
+ | H = HL % A ; Remainder | ||
+ | ENDIF | ||
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− | |||
− | |||
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'''Note:''' | '''Note:''' |
Revision as of 19:29, 9 November 2008
DIV = Divide
Hex | Mnemonic | Cycles |
---|---|---|
CE D9 | DIV HL, A | 52 |
Execute
; DIV HL, A ; ; HL is the Dividend ; A is the Divisor ; L will be the Quotient ; H will be the Remainder/Rest Ds = HL ÷ A IF Ds < 256 THEN L = Ds ; Quotient H = HL % A ; Remainder ENDIF
Note:
Can throw Division by Zero if Divisor is 0 (We need to research more about this)
If Quotient can't fit in 8-Bits range, Overflow flag will be set and the result won't be saved.
Description
16-Bits Register HL divide by 8-Bits Register A, Quotient will be stored at 8-Bits Register L and Remainder will be stored at 8-Bits Register H.
Conditions
Zero: Set when result is 0
Carry: Always Clear
Overflow: Set when Quotient can't fit in 8-Bits range
Sign: Set when 7th bit of Quotient is 1
Examples
; A = 0x02 ; HL = 0x0007 DIV HL, A ; L = 0x03 (0x0007 / 0x02 = 0x03 (with rest 0x01)) ; H = 0x01 (Remainder/Rest) ; F = (Zero = 0):(Carry = 0):(Overflow=0):(Sign=0)
; A = 0x00 ; HL = 0x0007 DIV HL, A ; (0x0007 / 0x00 = Division by Zero) ; HL = 0x???? (Unpredictable result!?) ; F = (Zero = ?):(Carry = ?):(Overflow=?):(Sign=?) ; - Throw Division by Zero Exception
; A = 0x02 ; HL = 0xFFFD DIV HL, A ; (0xFFFD / 0x02 = 0x7FFE (with rest 0x01)) ; HL = 0xFFFD (Results are unchanged since Quotient exceed 8-Bits range) ; F = (Zero = 0):(Carry = 0):(Overflow=1):(Sign=1)