Panasonic MN103S User Manual page 506

Chapter 16
Appendix
MACB (signed byte data multiply and accumulate instruction: register to register)
[Instruction format (macro name)]
MACB Dm, Dn
[Assembler mnemonic]
udf32 Dm, Dn
[Operation]
This instruction performs multiply and accumulate operation by means of the multiplier and the adder provided in
the extension arithmetic unit.
The instruction multiplies the content of Dm (signed 8-bit integer: multiplicand) by the content of Dn (signed 8-
bit integer: multiplier), adds this product to the 32-bit accumulative sum that is stored in the multiply and
accumulate register MCRL and stores the 32-bit result in the multiply and accumulate register MCRL.
The register outputs a multiply and accumulate overflow detection flag "1" to the register MCVF if the
accumulative sum data overflows beyond 32 bits during addition of the product and the accumulative sum.
[Flag changes]
Flag Change
V -
C -
N -
Z -
[Note for programming]
An instruction other than extension instructions that requires 1 or more cycles must be inserted between this
instruction and a next extension instruction.
XVI - 54 Extension Instruction Specification
Condition