Renesas RL78 Series User Manual page 659

RL78/G1D
16.4.5 Division operation
• Initial setting
<1> Set the multiplication/division control register (MDUC) to 80H.
<2> Set the dividend (higher 16 bits) to multiplication/division data register A (H) (MDAH).
<3> Set the dividend (lower 16 bits) to multiplication/division data register A (L) (MDAL).
<4> Set the divisor (higher 16 bits) to multiplication/division data register B (H) (MDBH).
<5> Set the divisor (lower 16 bits) to multiplication/division data register B (L) (MDBL).
<6> Set bit 0 (DIVST) of the MDUC register to 1.
(There is no preference in the order of executing steps <2> to <5>.)
• During operation processing
<7> The operation will end when one of the following processing is completed.
• A wait of at least 16 clocks (The operation will end when 16 clocks have been issued.)
• A check whether the DIVST bit has been cleared
(The read values of the MDBL, MDBH, MDCL, and MDCH registers during operation processing are not
guaranteed.)
• Operation end
<8> The DIVST bit is cleared and the operation ends. At this time, an interrupt request signal (INTMD) is generated
if the operation was performed with MACMODE = 0.
<9> Read the quotient (lower 16 bits) from the MDAL register.
<10> Read the quotient (higher 16 bits) from the MDAH register.
<11> Read the remainder (lower 16 bits) from multiplication/division data register C (L) (MDCL).
<12> Read the remainder (higher 16 bits) from multiplication/division data register C (H) (MDCH).
(There is no preference in the order of executing steps <9> to <12>.)
• Next operation
<13> Start with the initial settings of each step to change the operation mode. When the same operation mode is
used sequentially, settings <1> to <5> can be omitted.
Remark Steps <1> to <12> correspond to <1> to <12> in Figure 16-10.
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
CHAPTER 16 MULTIPLIER AND DIVIDER/MULTIPLY-ACCUMULATOR
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