Hardware requirements

  • Mini/micro USB cable

  • LPCXpresso51U68 board

  • NXP Mic/Audio/Oled (MAO) shield

  • Personal Computer

  • headphones with 3.5 mm stereo jack

  • source of sound (line output to 3.5 mm stereo jack)

Board settings

No special settings are required on LPCXpresso51U68 board. MAO shield should be mounted to LPCXpresso51U68 board. MAO shield - JP3 1-2 have to be connected.

Prepare the Demo

  1. Connect headphones to Audio HP / Line-Out connector of MAO shield.

  2. Connect source of sound(from PC or Smart phone) to Audio Line-In connector of MAO shield.

  3. Connect a micro USB cable between the PC host and the CMSIS DAP USB port (J6) on the board

  4. Open a serial terminal with the following settings (See Appendix A in Getting started guide for description how to determine serial port number):

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  5. Download the program to the target board.

  6. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

Headphones will play what is input into Audio Line-In connector of MAO shield. Terminal window will show:

Configure codec
Configure I2S
Setup digital loopback