Operations Of Multiplier/Divider; Multiplication Operation - NEC 78K0 User Manual

18.4 Operations of Multiplier/Divider

18.4.1 Multiplication operation

• Initial setting
1. Set operation data to multiplication/division data register A0L (MDA0L) and multiplication/division data
register B0 (MDB0).
2. Set bits 0 (DMUSEL0) and 7 (DMUE) of multiplier/divider control register 0 (DMUC0) to 1. Operation
will start.
• During operation
3. The operation will be completed when 16 internal clocks have been issued after the start of the
operation (intermediate data is stored in the MDA0L and MDA0H registers during operation, and
therefore the read values of these registers are not guaranteed).
• End of operation
4. The operation result data is stored in the MDA0L and MDA0H registers.
5. DMUE is cleared to 0 (end of operation).
6. After the operation, an interrupt request signal (INTDMU) is generated.
• Next operation
7. To execute multiplication next, start from the initial setting in 18.4.1 Multiplication operation.
8. To execute division next, start from the initial setting in 18.4.2 Division operation.
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CHAPTER 18 MULTIPLIER/DIVIDER
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User's Manual U15947EJ2V0UD