SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
The Thermal FSM is clocked by the 32KHz clock. At reset the FSM is not enabled and can be enabled by configuring the TOP_CTRL.TSENSE_CFG register.
Software needs to configure the below register bits to enable the Temperature Sensor:
By default these bits are set to 1, which disables the temperature sensor. To enable the temperature sensor these bits should be cleared (set to 0). Once the sensor is enabled, temperature measurement is initiated by enabling the FSM by writing 1 to TOP_CTRL.TSENSE_CFG.ENABLE.
Once enabled, the FSM will read out the temperature values from the sensors in a round robin fashion based on TOP_CTRL.TSENSE_CFG.SENSOR_SEL bitfield value. TOP_CTRL.TSENSE_CFG.SENSOR_SEL controls the enabling/disabling of individual sensors.
For each selected sensor, FSM requires anywhere between 51 to 54 clock cycles to start the sequence and register the result into TOP_CTRL.TSENSE*_RESULT.DTEMP register. TOP_CTRL.TSENSE_CFG.DELAY configures the number of clock cycles between end of result captured to FSM starting the sequence for the next enabled sensor. When the conversion is ongoing for a particular sensor, the corresponding TOP_CTRL.TSENSE*_RESULT.EOCZ status bits are set to 1. The EOCZ bit is reset to 0 again when the conversion completes. After this the valid temperature is written automatically by FSM in the TOP_CTRL.TSENSE*_RESULT.DTEMP bit fields, and then software is able to read it from the corresponding register. Figure 6-15 describes the sequence of sensor measurement based on SENSOR_SEL bits.