New CPU Core Boosts Performance for Renesas MCUs

Renesas Electronics has announced the development of its third-generation 32-bit RX CPU core, the RXv3. The RXv3 CPU core will be employed in Renesas’ new RX microcontroller families that begin rolling out at the end of 2018. The new MCUs are designed to address the real-time performance and enhanced stability required by motor control and industrial applications in next-generation smart factory, smart home and smart infrastructure equipment.

The RXv3 core boosts CPU core architecture performance with up to 5.8 CoreMark/MHz, as measured by EEMBC benchmarks, to deliver industry-leading performance, power efficiency and responsiveness. The RXv3 core is backwards compatible with the RXv2 and RXv1 CPU cores in Renesas’ current 32-bit RX MCU families. Binary compatibility using the same CPU core instruction sets ensures that applications written for the previous-generation RXv2 and RXv1 cores carry forward to the RXv3-based MCUs. Designers working with RXv3-based MCUs can also take advantage of the robust Renesas RX development ecosystem to develop their embedded systems.
The RX CPU core combines a design optimized for power efficiency and a fabrication process producing excellent performance. The new RXv3 CPU core is primarily a CISC (Complex Instruction Set Computer) architecture that offers significant advantages over the RISC (Reduced Instruction Set Computer) architecture in terms of code density. RXv3 utilizes a pipeline to deliver high instructions per cycle (IPC) performance comparable to RISC. The new RXv3 core builds on the proven RXv2 architecture with an enhanced pipeline, options for register bank save functions and double precision floating-point unit (FPU) capabilities to achieve high computing performance, along with power and code efficiency.

The enhanced RX core five-stage superscalar architecture enables the pipeline to execute more instructions simultaneously while maintaining excellent power efficiency. The RXv3 core will enable the first new RX600 MCUs to achieve 44.8 CoreMark/mA with an energy-saving cache design that reduces both access time and power consumption during on-chip flash memory reads, such as instruction fetch.

The RXv3 core achieves significantly faster interrupt response times with a new option for single-cycle register saves. Using dedicated instruction and a save register bank with up to 256 banks, designers can minimize the interrupt handling overhead required for embedded systems operating in real-time applications such as motor control. RTOS context switch time is up to 20 percent faster with the register bank save function.

The model-based development (MBD) approach has penetrated various application developments; it enables the DP-FPU to help reduce the effort of porting high precision control models to the MCU. Similar to the RXv2 core, the RXv3 core performs DSP/FPU operations and memory accesses simultaneously to substantially boost signal processing capabilities.

Renesas plans to start sampling shipments of RXv3-based MCUs before the end of Q4 2018.

Renesas Electronics |