SWCU192 November 2021 CC1312R7 , CC1352P7 , CC2652P7 , CC2652R7
20.4.5.1 Introduction
The AUX TDC (AUX_TDC) peripheral is a high-precision TDC used to measure the time between a configurable start event and another configurable stop event. The TDC counts at either 96 MHz or 48 MHz, using both edges of a selected counter clock source.
TDC peripheral features are:
- Configurable counter clock source
- Configurable reference clock source for on-chip clock calibration
- Configurable start event source and polarity
- Configurable stop event source and polarity
- Optional prescaling of start and stop events:
- The prescaler can also be used for standalone, asynchronous pulse counting.
- Optional stop event ignore counter:
- Several periods can be measured during a single TDC conversion.
- 25-bit TDC conversion counter with configurable saturation limit
- TDC measurement-done event
The TDC is typically used for the following:
- Frequency measurements
- Capacitive sensing, in conjunction with the analog AUX peripherals ISRC and COMPA
- Precise time between arbitrary event measurements
- Standalone, asynchronous pulse counting using the prescaler
The Sensor Controller and the System CPU share the TDC peripheral. TI-RTOS uses the TDC peripheral for RCOSC calibration. Both masters must implement and honor resource sharing to use this peripheral. For details, see Section 20.4.3.3.
Figure 20-15 shows the block diagram of the TDC. It also shows the connections to the Oscillator Control (OSCCTL) module, which requires configuration to use the TDC.
Figure 20-15 AUX_TDC Block Diagram