WDT timeout
This example shows how to generate a Watchdog timer reset by emulating a deadlock.
Description
This example application shows how the WDT peripheral library resets the watchdog timer by not feeding the watchdog on switch press. The application sets up the watchdog to reset the device. The application also sets up the timer to blink an LED to emulate a process. A user switch press forces the device to wait in an infinite loop to emulate a deadlock. As a result a device reset is triggered as the watchdog counter overflows the bounded value.
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/wdt/wdt_timeout/firmware .
To build the application, refer to the following table and open the project using its IDE.
| Project Name | Description |
|---|---|
| sam_e70_xult.X | MPLABX Project for SAM E70 Xplained Ultra board |
| sam_v71_xult.X | MPLABX Project for SAM V71 Xplained Ultra board |
Setting up the hardware
The following table shows the target hardware for the application projects.
| Project Name | Board |
|---|---|
| sam_e70_xult.X | SAM E70 Xplained Ultra board |
| sam_v71_xult.X | SAM V71 Xplained Ultra board |
Setting up SAM E70 Xplained Ultra board
- Connect the Debug USB port on the board to the computer using a micro USB cable
Setting up SAM V71 Xplained Ultra board
- Connect the Debug USB port on the board to the computer using a micro USB cable
Running the Application
- Open the Terminal application (Ex.:Tera term) on the computer
- Connect to the EDBG Virtual COM port and configure the serial settings as follows:
- Baud : 115200
- Data : 8 Bits
- Parity : None
- Stop : 1 Bit
- Flow Control : None
- Build and Program the application project using its IDE
-
LED should be blinking and the console displays the following message
- Press the switch to put the system in a deadlock
-
LED should stop blinking and the console should print the following message
- WDT will reset the device in four seconds and the demonstration should restart
The following table provides the LED and switch names
| Board | LED | Switch |
|---|---|---|
| SAM E70 Xplained Ultra board | LED1 | SW0 |
| SAM V71 Xplained Ultra board | LED0 | SW0 |