1.34 TC Compare Mode
This example shows how to use the TC module in compare mode to generate an active low, active high, and toggle output on compare match.
Description
Three TC channels are configured in compare mode. Each channel generates different output waveform depending upon configured action on compare match and period match.
Active low output: Output is set high on compare 1 match and is set low on compare 0 match.
Active high output: Output is set low on compare 1 match and is set high on compare 0 match.
Toggle output: Output toggles on compare 0 match.
Downloading and Building the Application
To clone or download this application from Github, go to the main page of this repository and then click Clone button to clone this repository or download as zip file. This content can also be downloaded using content manager by following these instructions.
Path of the application within the repository is apps/tc/tc_compare_mode/firmware.
To build the application, refer to the following table and open the project using its IDE.
| Project Name | Description |
|---|---|
| sam_l21_xpro.X | MPLABX project for SAM L21 Xplained Pro Evaluation Kit |
Setting Up the Hardware
The following table shows the target hardware for the application projects.
| Project Name | Description |
|---|---|
| sam_l21_xpro.X | SAM L21 Xplained Pro Evaluation Kit |
Setting Up SAM L21 Xplained Pro Evaluation Kit
- Connect the Debug USB port on the board to the computer using a micro USB cable
Running the Application
- Build and Program the application using its IDE
- Observe generated waveforms on the oscilloscope
SAM L21 Xplained Pro Evaluation Kit:
| Timer Channel | Pin | Observable Characteristic of the Waveform |
|---|---|---|
| TC0_WO1 | PB13 (Pin 8 of EXT2) | Active high output with frequency 75 Hz |
| TC3_WO1 | PA21 (Pin 6 of EXT2) | Active low output with frequency 75 Hz |
| TC4_WO0 | PA18 (Pin 14 of EXT2) | Toggle output with frequency 37.5 Hz |