Floating Point Unit (FPU) Support

The Arm Cortex-M33 processor has support for hardware floating point calculations. The SDK samples and libraries use floats. Therefore, the FPU is powered on whenever the device is in Run Mode.

In low power modes, power to the FPU is appropriately adjusted for each mode, as follows:

  • In Sleep Mode when core retention is disabled by the application firmware, the FPU is not powered, so firmware does not need power down the FPU.
  • In Sleep Mode when core retention is enabled, firmware powers down the FPU before entering sleep, and powers up the FPU again on wakeup.
  • In Standby Mode, the power consumption of the FPU is negligible, so it is left powered on.