ARM outs resource-rich MCU aimed at wearable IoT devices

ARM has introduced a resource-rich MCU geared for wearables. The Cortex-A32 processor combines a processor architecture and process technology that touts 25 per cent more efficient 32bit core in as little as 0.25mm² of silicon.

The Cortex-A32 is built on ARM's ARMv8-A architecture and represents an upgrade path for the popular A-5 and A7 architectures used in many 32bit application processors. Not only does it offer higher performance for lower power than the A7, the A32 increases the resources available for handling 32bit applications. More than 100 32bit instructions have been added to the A32's architecture, including enhancements for media performance, software encryption and floating point calculations.

The A32 is designed for scalability to address a range of applications. At the high end, a quad-core device can operate at GHz clock speeds, consuming less than 75mW per core. In its smallest configuration, a 100MHz single-core A32 with AMBA interface and 8k each of instruction and data cache takes less than 4mW of power.

Figure 1: More than 100 32bit instructions have been added to the Cortex-A32 processor's architecture, including enhancements for media performance, software encryption and floating point calculations.

The A32 can offer the kind of performance needed in industrial applications such as gateways, robotics and edge devices with local data analytics and control responsibilities. But the combination of rich resources and low power also make the A32 suitable for challenging wearable IoT applications. Smart watches, health monitors and the like must be very power efficient in order to minimise user frustration around frequent battery charging or replacement. They also require sophisticated graphical interfaces, robust operating systems and significant sensor processing capabilities in order to provide the functionality and rich user interface users demand. The A32 was designed to meet these seemly mutually exclusive requirements.

According to Zach Shelby, ARM's VP of marketing for IoT, the new generation of processors that the A32 core will enable aligns well with the trends he sees emerging in IoT and other embedded design. "Things are changing in the embedded design world," Shelby said. "There are expectations coming in from other industries for systems to have sophisticated, complete software foundations so that developers don't spend time assembling the pieces, just writing their application code." This kind of platform-level foundation requires operating systems and other types of hardware abstraction, such as supporting Java or Python programming language. The performance of the A32 core helps support creating such foundations in a wearable IoT design for follow-on developers to springboard from.

As yet, though, only the core is being announced. ARM doesn't make chips and none of ARM's licensees that do make chips have released products that use the core. So, developers will need to wait a bit longer for the A32 to be available as a design choice. Not too long, though. History has shown that chips shouldn't be too far behind an ARM core announcement.

- Richard Quinnell
  EDN