32172 datasheet(24/875 Pages) RENESAS

24 / 875 page

1-3

Rev.1.0

Overview

1.1 Overview

1.1.2 Built-in Multiply-Accumulate Operation Function

(1) Built in high-speed multiplier

• The M32R incorporates a 32-bit x 16-bit high-speed multiplier/accumulator which allows the

processor to execute a 32-bit x 32-bit integer multiplication instruction in three cycles (one

cycle is 25 ns when CPU memory clock = 40 MHz).

(2) Supports Multiply-Accumulate operation instructions comparable to DSP

• The M32R supports the following four modes of Multiply-Accumulate operation instructions (or

multiplication instructions) based on a 56-bit accumulator:

16 high-order register bits x 16 high-order register bits

16 low-order register bits x 16 low-order register bits

All 32 register bits x 16 high-order register bits

All 32 register bits x 16 low-order register bits

• The M32R has instructions to round off the value stored in the accumulator to 16 or 32 bits, as

well as instructions to shift the accumulator value to adjust digits and store the digit-adjusted

value in a register. These instructions also can be executed in one cycle, so that when

combined with high-speed data transfer instructions such as Load & Address Update and

Store & Address Update, they enable the M32R to exhibit high data processing capability

comparable to that of DSP.

1.1.3 Built-in Flash Memory and RAM

• The 32172/32173 contains flash memory and RAM that can be accessed with no wait states,

making it possible to build a high-speed embedded system.

• The internal flash memory allows for on-board programming (you can write to it while being

mounted on the printed circuit board). Use of flash memory means the chip engineered at the

development phase can be used directly in mass-production, so that you can smoothly migrate

from prototype to mass-production without changing the printed circuit board.

• The internal flash memory can be rewritten 100 times.

• The internal flash memory has a virtual-flash emulation function, allowing the internal RAM

tobe artificially mapped into part of the internal flash memory. This function, when combined

with the internal Real-Time Debugger (RTD), facilitates data tuning on ROM tables.

• The internal RAM can be accessed for read or rewrite from an external device independently of

the M32R by using RTD (real-time debugger). It is communicated with external devices by

RTD's exclusive clock-synchronized serial I/O.

32172 Datasheet(PDF) 24 Page - Renesas Technology Corp