Helium vector technology adds ML and DSP capabilities for upgrading Cortex-M4 and Cortex-M33 microcontroller designs.
Arm has added the Cortex-M42 processor to its Arm Flexible Access and Arm Total Access portfolios, extending access to machine learning (ML) and digital signal processing (DSP) capabilities for embedded devices. The processor targets applications with constraints on power consumption, silicon area and cost.
Arm Flexible Access and Arm Total Access provide silicon partners with processor designs and supporting technologies for different performance, power and cost requirements. The addition of Cortex-M42 gives partners another option for developing AI-enabled microcontrollers (MCUs) and connected devices.
Adding ML and DSP capabilities to Cortex-M designs
Cortex-M42 combines Arm Helium technology with a compact, AHB-based design to support upgrades from existing Cortex-M4- and Cortex-M33-based MCUs. Target applications include audio processing and keyword spotting in wearables, sensor analysis, condition monitoring and signal processing in connectivity and industrial controllers.
The processor also supports distributed embedded processing for sensing, anomaly detection, predictive maintenance and control in physical AI systems. For example, it could perform local signal processing and condition monitoring for robotic motors and joints to identify abnormal behavior or equipment wear, without handling safety-critical motion-control functions.
Built on the Armv8.1-M architecture, Cortex-M42 provides up to three times the vector compute capability and twice the vector power efficiency of Cortex-M33, according to Arm. Arm Custom Instructions allow workload-specific processor optimization. Other technologies added to Arm Flexible Access include Cortex-M52, Cortex-M55, Cortex-M85, the Ethos-U85 NPU, the Corstone-320 reference design platform and the Armv9 Edge AI platform.
Access programs and partner designs
As of November 2026, Arm Flexible Access has 319 active members and has supported more than 500 unique tape-outs. Arm Total Access has 60 partners, with more than 600 projects undertaken through the program since its launch.
Arm Flexible Access offers low- or no-cost access to processor designs, development tools and technical resources, allowing companies to explore and develop products before committing to a final design. Arm Total Access supports established semiconductor companies, OEMs, ODMs and system integrators in developing, commercializing and scaling products across different applications and performance requirements.
Partners in both programs use Arm processor technologies and the associated software ecosystem to develop silicon for their target applications.
Recent partner tape-outs include:
- EnSilica: Uses Arm Cortex processors and Ethos NPUs to develop custom ASICs for communications, satellite, automotive and industrial applications.
- Nordic Semiconductor: Uses Cortex-M33 in its nRF54LM20B for low-power wireless and connected devices.
- Synaptics: Combines Cortex-M52 and Ethos-U55 in its SRW1500 series for embedded AI processing. Its Astra SR80 series uses Cortex-M33 for power-sensitive connected applications.
The addition of Cortex-M42 expands the processor options available through both access programs for local AI and signal processing. It provides a development path for Cortex-M4- and Cortex-M33-based designs that require additional ML and DSP capabilities.
For more information, visit arm.com.
