Renesas' New RTOS-Supported MPUs Enable High-Definition HMI and Fast Startup

By Taryn Engmark

Associate Editor

Embedded Computing Design

August 23, 2022


Renesas' New RTOS-Supported MPUs Enable High-Definition HMI and Fast Startup

Renesas Electronics Corporation's RZ/A3UL group of microprocessors (MPU) enables a high-definition human-machine interface (HMI) and quick startup for applications that require high throughput and real-time capabilities.

The new RZ/A3UL utilizes the benfits of a real-time operating system (RTOS) alongside a 64-bit Arm® Cortex®-A55 CPU core with a maximum operating frequency of 1 GHz. An RTOS allows a system to start under one second after boot-up, which is helpful for systems that require rapid response times (e.g., industrial and office automation equipment with liquid crystal displays or control panels, or audio equipment and POS terminals).

The RZ/A3UL MPUs include an Octal-SPI memory interface*1, which helps keep board designs simple and compact. Versions of the new MPUs also support a DDR3L/DDR4 memory interface that enables a high-speed DRAM connection at data transfer speeds up to 10x faster than the Octal-SPI interface. The performance levels achieved with that high data transfer speed enables an HD (1280x720) class display and a sophisticated, interactive HMI utilizing input from a camera or other sensor.

The RZ/A3UL supports FreeRTOS — available in Renesas' Flexible Software Package with HAL drivers — and Azure RTOS. Renesas is a license provider of Azure RTOS for the RZ Family, so users are able to access and download Azure RTOS from GitHub. An extensive suite of middleware is also available for both operating systems.

The compatibility of package pin assignments and peripheral functions between the RZ/A3UL, RZ/G2UL (whose Cortex-A55 targets Linux-based HMI applications), and RISC-V-based RZ/Five products allows engineers to develop different products on the same board design — all they need to do is swap out the chip. Engineers can also leverage this compatibility to transition between products that utilize an RTOS to Linux-based products, ensuring efficient development across different product models.

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