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# 1.4 ADC User Sequence

This example application shows how to sample three analog inputs using the user sequencer in external trigger mode (TC peripheral) and send the converted data to the console.

## Description

Conversion of the three analog inputs is triggered by TC peripheral at every 500 ms. The user sequencer is used to define the order of conversion:

Board | Sequence of conversion
--- | ---
SAMA7D65 Curiosity Board | MPLABX project for SAMA7D65 Curiosity Board
SAMA7D65 Curiosity Pro Board | MPLABX project for SAMA7D65 Curiosity Pro Board

Analog input voltage in the range of 0V to 3.3V is fed to the ADC input channel AD0, AD3 and AD1. ADC conversion result is displayed on the console.

## 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_user_sequence .

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
- Use a jumper wire to connect Pin 11 of RPi connector (AD0 is mapped to Port Pin PC3) to 3.3V or GND
- Use a jumper wire to connect Pin 13 of RPi connector (AD1 is mapped to Port Pin PC4) to 3.3V or GND
- Use a jumper wire to connect Pin 5 of RPi connector (AD3 is mapped to Port Pin PC6) to 3.3V or GND

### 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
- Use a jumper wire to connect Pin 11 of RPi connector (AD0 is mapped to Port Pin PC3) to 3.3V or GND
- Use a jumper wire to connect Pin 13 of RPi connector (AD1 is mapped to Port Pin PC4) to 3.3V or GND
- Use a jumper wire to connect Pin 5 of RPi connector (AD3 is mapped to Port Pin PC6) to 3.3V or GND

## 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. The console displays the ADC Count and the ADC Input Voltage.

Rev: C