4.6.4 Sharing Resources Between the Sensor Controller and the Cortex^®-M3

Users can access several resources like the OSC_DIG, TDC, and ADC on the CC26x0 and CC13x0 devices from both the sensor controller and the Cortex-M3. To ensure these accesses are correctly arbitrated on the bus, the Cortex-M3 should always access these modules through driverlib, which has this arbitration support built in.

If the Cortex-M3 and the sensor controller access the same resources, protect them using the auxiliary semaphore module. This module has eight semaphores reserved for protecting-shared resources in the auxiliary domain.

The convention is as follows:

• SMPH0 protects Adi/Ddi bus. This semaphore is built into CC26xxware and CC13xxware implementations.
• SMPH1 protects the TDC. The application enforces this.
• SMPH2 protects the ADC. The application enforces this.

For details on how to use the auxiliary semaphores, see the AUX_SMPH registers.