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:

BoardSequence of conversion
SAMA7G54 Evaluation KitAD6 –> AD7 –> AD5

Analog input voltage in the range of 0 V to 3.3 V is fed to the ADC input channel AD6, AD7 and AD5. 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/firmware .

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

Project NameDescription
sam_a7g5_ek.XMPLABX project for SAMA7G54 Evaluation Kit

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 NameDescription
sam_a7g5_ek.XSAMA7G54 Evaluation Kit

Setting Up SAMA7G5 Evaluation Kit

SETTING UP THE BOARD
  • Connect the USB port J7 on board to the computer using a micro USB cable (to power the board)
  • Connect the USB port J24 on board to the computer using a micro USB cable (to enable debug com port)
  • Use a jumper wire to connect Pin 11(SDA) of mikroBUS 2 connector (AD5 is mapped to Port Pin PC18) to 3.3V or GND
  • Use a jumper wire to connect Pin 12(SCL) of mikroBUS 2 connector (AD6 is mapped to Port Pin PC19) to 3.3V or GND
  • Use a jumper wire to connect Pin 15(INT) of mikroBUS 2 connector (AD7 is mapped to Port Pin PC20) 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 Jlink 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