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# 1.25 RTC Alarm Interrupt

This example application shows how to use the RTC to configure the time and generate the alarm.

## Description

This example application shows how to setup system time and configure alarm using the RTC Peripheral Library. The application sets up an alarm to be generated after 20 seconds of the configured system time. The application displays a message on the alarm trigger.

## 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/rtc/rtc_alarm.

To build the application, refer to the following table and open the project using its IDE.

Project Name | Description
--- | ---
sam_a7d65_curiosity.X | MPLABX project for SAMA7D65 Curiosity Board
sam_a7d65_curiosity_pro.X | MPLABX project for SAMA7D65 Curiosity Pro 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_a7d65_curiosity.X | SAMA7D65 Curiosity Board
sam_a7d65_curiosity_pro.X | SAMA7D65 Curiosity Pro Board

### Setting Up SAMA7D65 Curiosity Board

Setting up the board:

- Connect the USBA port J3 on the board to the computer using a Type-C USB cable (to power the board)
- Connect the UART Debug port (J35) on the board to the computer using a FTDI-USB cable

### Setting Up SAMA7D65 Curiosity Pro Board

Setting up the board:

- Connect the USBA port J1 on the board to the computer using a Type-C USB cable (to power the board)
- Connect the UART Debug port (J63) on the board to the computer using a FTDI-USB cable

## Running the Application

1. Open the Terminal application (Ex.: Tera term) on the computer.
2. Connect to the Virtual COM port and configure the serial settings as follows:
   - Baud: 115200
   - Data: 8 Bits
   - Parity: None
   - Stop: 1 Bit
   - Flow Control: None
3. Build and program the application using its IDE.
4. The console displays the current time and the alarm time (System time starts at 12:00:00 and gets updated every second).
5. Once the alarm time is reached, it print the alarm message and turns on the LED (System time keeps updating).

Refer to the following table for LED name:

Board | LED Name
--- | ---
SAMA7D65 Curiosity Board | RGB_LED (Green)
SAMA7D65 Curiosity Pro Board | RGB_LED (Green)

Rev: C