1.23 PWM Channels
This example demonstrates how to use the PWM peripheral to generate PWM signals.
Description
This example shows how to configure the PWM to generate PWM signals whose duty and period can be configured independently.
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/pwm/pwm_channels/firmware.
To build the application, refer to the following table and open the project using its IDE.
| Project Name | Description |
|---|---|
| sam_9x75_curiosity.X | MPLABX project for SAM9X75 Curiosity Development Board |
Setting Up AT91Bootstrap Loader
To load the application binary onto the target device, we need to use at91bootstrap loader. Refer to the at91bootstrap loader documentation for details on how to configure, build and run bootstrap loader project and use it to bootstrap the application binaries.
Setting Up the Hardware
The following table shows the target hardware for the application projects.
| Project Name | Description |
|---|---|
| sam_9x75_curiosity.X | SAM9X75 Curiosity Development Board |
Setting Up SAM9X75 Curiosity Development Board
- Connect the UART DEBUG J35 on board to the computer using a UART-FTDI cable (to enable debug com port)
- Connect the USB port J2 on board to the computer using a micro USB cable (to power the board)
- Connect PWM (PC21) PIN of mikroBUS connector to an oscilloscope/Logic analyzer
Running the Application
- Build the application using its IDE
- Open the Terminal application (Ex.:Tera term) on the computer.
- Connect to the (USB to Serial) COM port and configure the serial settings as
follows:
- Baud : 115200
- Data : 8 Bits
- Parity : None
- Stop : 1 Bit
- Flow Control : None
- PWM3 generates an active high PWM signal with 100ms period and 75% duty on PWM (PC21) PIN of mikroBUS connector
- Whenever a counter event occurs on PWM channel 0, console is updated as
follows:
RGB_LED pulses with Greenish hue as PWM3 signal is connected to the cathode of the RGB LED.