Key Specs of the STM32MP1 Microprocessor Series
Building on the success of its STM32 microcontroller families, earlier this year ST announced the company’s first Microprocessor (MPU) series: the STM32MP1. These general-purpose multicore microprocessors will help facilitate development of high-performance solutions across a broad range of application areas. At the recent ST Developers Conference, ST’s Mike Hartmann provided a detailed presentation on the STM32MP1 and the series’ features and capabilities.
The STM32MP1 offers a flexible architecture for applications, including home appliances, consumer and personal electronics, medical devices and industrial systems. ST is not targeting automotive applications with the STM32MP1, as the company has a dedicated automotive product group with specially designed and qualified automotive MCUs. Of particular interest to developers targeting long-lived industrial applications, the STM32MP1 carries with it a rolling 10-year longevity commitment that provides designers, product managers and procurement teams the assurance that components will remain available throughout the lifecycle of their design.
A flexible architecture with a rich feature set
The STM32MP1 series is based on a single- or dual-Arm® Cortex®-A7 and Cortex®-M4 core architecture. The Cortex-A7 core provides access to open-source operating systems (Linux/Android) and offers high-performance processing, while the Cortex-M4 core leverages the STM32 MCU ecosystem and is dedicated to real-time processing and low-power tasks.
In the STM32MP1, the Cortex-A7 cores are clocked at 650MHz, and are accompanied by a 32-Kbyte L1 instruction cache, 32-Kbyte Level 1 data cache, and 256-Kbyte Level 2 cache. The A7s also come with Arm Neon SIMD architecture extensions for accelerating multimedia and signal-processing algorithms.
For real-time, low-power processing, the Cortex-M4 core runs at 209MHz, with a single-precision floating point unit (FPU), a full set of digital signal processor (DSP) instructions, and a memory protection unit (MPU) for enhanced application security.
The STM32MP1 also features an optional OpenGL-compliant 3D GPU for advanced HMI development that runs at 533MHz. It offers DDR and LPDDR interfaces that also clock at 533MHz, with 256KB of system RAM, plus 384KB of MCU RAM and 64KB of retention RAM, which facilitate the Cortex-M4’s real-time processing and low-power mode operations.
With an eye on secure operations, the STM32MP1 offers a robust security toolbox, including Arm’s TrustZone technology, which provides system-wide hardware isolation for trusted software. The STM32MP1 also features a hardware cryptographic option, secure RAM and ROM, tamper resistance and secure real-time clock. It also offers 16- and 32-bit controls and timers, and for analog inputs, two full 16-bit AD converters with up to 22 channels.
The STM32MP1 offers nearly 20 connectivity interfaces for a wide range of cameras, displays, Ethernet, USBs, HDMI, and UARTs. For design flexibility, most peripherals can be allocated to either the Cortex-A7 or Cortex-M4 cores.
Power management and efficiency
In addition to the processor, the STM32MP1 offers a companion power-management IC, the STPMIC1, to simplify design and optimize power consumption. At full power, the dual Cortex-A7s running at 650MHz generate 2470 DMIPS for graphic and communication processing. Also at full power, the Cortex-M4 at 209MHz generates 260 DMIPS for motor control, sensor acquisition, and lower power operations. With both cores operating at full speed, the STM32MP1 still delivers very good power efficiency, drawing just 353mW.
For dynamic power efficiency, the Cortex-A7 and Cortex-M4 cores can be operated or stopped independently to achieve the best power efficiency for each processing and real-time application requirement. As a System-on-Chip, the STM32MP1 offers a number of low-power modes, including:
- Motor control and sensing mode, with the Cortex-A7 shut down but the Cortex-M4 in operation for sensor acquisition and low-power operations, drawing 92mW.
- Standby mode, with both cores turned off but RAM in self-refresh, drawing 36µW.
- VBAT mode, with the real-time clock in operation, drawing 4.5 µW, while keeping the system secure thanks to the tamper detect feature.
The STM32MP1 can go from Standby Mode to running both cores in around a second.
Software, tools, and availability
As for software, the Cortex-A7 operates on the OpenSTLinux Distribution, a fully mainlined Linux distribution for Cortex-A7 cores that’s fully compliant with open-source standards. The Cortex-M4 is supported by the STM32 ecosystem, including the STM32Cube, a comprehensive software solution combining embedded software libraries, including hardware abstraction layer peripheral driver and other components, and the STM32CubeMX, its graphical interface for configuring the embedded firmware. ST has also released a selection of discovery and evaluation boards to speed up evaluation, prototyping, and design using the STM32MP1.
Beyond this, the STM32MP1 is supported by a broad ecosystem of ST partners to help with development of graphics user interfaces, security and training, and services.
- STM32MP157: Dual Cortex-A7 cores @ 650 MHz, Cortex-M4 core @ 209 MHz, 3D GPU, DSI display interface and CAN FD
- STM32MP153: Dual Cortex-A7 cores @ 650 MHz, Cortex-M4 core @ 209 MHz and CAN FD
- STM32MP151: Single Cortex-A7 core @ 650 MHz, Cortex-M4 core @ 209 MHz