STM32MP1 Primer – Day 3

The STM32MP157x dual core design pairs up a powerful Linux-enabled Cortex-A7 MPU with a speedy Cortex-M4 MCU. At first glance one would think that the Cortex-M4 is a luxury as the Cortex-A7 is fully capable of handling complex applications without any help from the Cortex-M4. However, the Cortex-A7 running under the control of a Linux kernel is not very good when it comes to precise millisecond and microsecond timing within the application. On the other hand, the Cortex-M4 can turn on a microsecond. An ideal situation would exist if we could run our heavy application loads using the Cortex-A7 and use the Cortex-M4 as a real-time coprocessor for the tasks that require more accurate time resolution. The application we will build in today's lecture will enable an interprocessor communications link between the Cortex-A7 and the Cortex-M4 cores.