Overview
========
The SAI Demo application demonstrates complicated digital audio playback and record case. The demo provide these features below:
1. Duplex audio transfer, record and playback at same time.
2. Playback a 250 Hz sine wave data generated by CMSIS-DSP library. Also compute the fundamental frequency using Fast Fourier Transform with CMSIS-DSP library.

Toolchain supported
===================
- Keil MDK  5.30
- GCC ARM Embedded  9.2.1
- MCUXpresso  11.2.0
- IAR embedded Workbench  8.50.1

Hardware requirements
=====================
- Mini/micro USB cable
- EVK-MIMXRT1060 board
- Personal Computer
- Headphone(OMTP standard)
- SD card

Board settings
==============
No special settings are required.

Prepare the Demo
================
1.  Connect a USB cable between the host PC and the OpenSDA USB port on the target board.
2.  Open a serial terminal with the following settings:
    - 115200 baud rate
    - 8 data bits
    - No parity
    - One stop bit
    - No flow control
3.	Insert SD card to card slot
4.  Download the program to the target board.
5.  Insert the headphones into the headphone jack on EVK-MIMXRT1060 board (J12).
6.  Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo
================
Note: This demo uses both headphone mic and board main mic(P1) as input source. The headphone mic provides left
channel data, and main mic (P1) provides right channel data. If users found there is noise while do record operation,
most probably it is the headphone standard issue (OMTP and CTIA standard difference). should use the OMTP
standard headphone. You can disable the left channel
by using an headphone without microphone feature.
This following section shows how to run the demo:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SAI Demo started!
Please insert a card into board.

Card inserted.

Make file system......The time may be long if the card capacity is big.

Create directory......
Please choose the option :
1. Record and playback at same time
2. Playback sine wave
3. Record to SDcard, after record playback it
4. Quit
Customization options
=====================

