R0K561668S000BE Renesas Electronics America, R0K561668S000BE Datasheet - Page 192

• Manufacturer Part Number: R0K561668S000BE
• Description: KIT STARTER FOR H8SX/1668
• Manufacturer: Renesas Electronics America
• Series: H8®r
• Type: MCUr

Specifications of R0K561668S000BE

• For Use With/related Products: H8SX/1668
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Contents: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed

Section 2 Instruction Descriptions
2.2.64
MAC
Multiply and ACcumulate
[1] Assembly-Language Format
MAC @ERn+, @ERm+
[2] Operation
(EAn) × (EAm) + MAC register → MAC register
ERn + 2 → ERn
ERm + 2 → ERm
[3] Operand Size

[4] Description
This instruction performs signed multiplication on two 16-bit operands at addresses given by the
contents of general registers (ERn and ERm), adds the 32-bit result to the contents of the MAC
register, and stores the sum in the MAC register. After this operation, ERn and ERm are both
incremented by 2. The operation can be carried out in saturating or non-saturating mode,
depending on the MACS bit in the system control register (SYSCR).
In non-saturating mode, MACH and MACL are concatenated to store a 42-bit result. The value of
bit 41 is copied into the upper 22 bits of MACH as a sign extension.
In saturating mode, only MACL is valid, and the result is limited to the range from H'80000000
(minimum value) to H'7FFFFFFF (maximum value). If the result overflows in the negative
direction, H'80000000 (minimum value) is stored in MACL. If the result overflows in the positive
direction, H'7FFFFFFF (maximum value) is stored in MACL. The LSB of MACH indicates the
status of the overflow flag (V-MULT) in the multiplier. Other bits retain their previous contents.
For details, see the hardware manual for the corresponding product.
This instruction is available only when the multiplier is supported.
[5] Condition Code
I
UI H
U
N
Z
V
C
—
—
—
—
—
—
— —
H: Previous value remains unchanged.
Rev. 4.00 Sep. 18, 2008 Page 174 of 914
REJ09B0102-0400