Overview
========
The spi_interrupt_b2b_slave example shows how to use spi functional API to do interrupt transfer as a slave:

In this example, the spi instance as slave. Slave receives data froma master and send a peiece of data to master,
and check if the data slave received is correct. This example needs to work with spi_interrupt_b2b_master example.

Toolchain supported
===================
- IAR embedded Workbench  8.32.3
- Keil MDK  5.27
- GCC ARM Embedded  8.2.1
- MCUXpresso  11.0.0

Hardware requirements
=====================
- Micro USB cable
- Two LPCXpresso55s69 boards
- Personal Computer

Board settings
==============
SPI one board:
Transfer data from SPI slave interface on board to 
other SPI interface on other board
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Master_board(SPI7)           Slave_board(SPI7)                          
Pin Name   Board Location     Pin Name   Board Location                     
MISO       P17  pin 12          MISO      P17  pin 12
MOSI       P17  pin 10          MOSI      P17  pin 10
SCK        P17  pin 14           SCK      P17  pin 14
SSEL1      P17  pin 1          SSEL1      P17  pin 1
GND        P17  pin 7           GND       P17  pin 7                        
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Prepare the Demo
================
1.  Connect a micro USB cable between the PC host and the LPC-Link USB port (P6) on the 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.  Download the program to the target board.
4.  Reset the SoC and run the project.

Running the demo
================
When the demo runs successfully, the log would be seen on the terminal like:

​~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SPI board to board interrupt slave example started!

SPI transfer finished!
​~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Customization options
=====================

