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# 1.3 ADC Polling

This example application shows how to sample an analog input in Polled mode and send the converted data to console.

## Description

In this example, Analog input voltage in the range of 0V to 3.3V is fed to the ADC and converted value is displayed on the console. The ADC conversion is triggered by software and result is polled using status API.

## 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/adc/adc_polled_mode.

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
- AD0 pin is used for analog input
- Use a jumper wire to connect Pin 11 of RPi connector (AD0 is used for input and is mapped to Port Pin PC3) to 3.3V or GND (OR Use Potentiometer to vary input voltage from GND to 3.3V and vice versa)

### 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
- AD0 pin is used for analog input
- Use a jumper wire to connect Pin 11 of RPi connector (AD0 is used for input and is mapped to Port Pin PC3) to 3.3V or GND (OR Use Potentiometer to vary input voltage from GND to 3.3V and vice versa)

## Running the Application

1. Build the application using its IDE.
2. Open the Terminal application (Ex.: Tera term) on the computer.
3. 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
4. Console displays ADC Count and ADC Input Voltage.

Rev: C