Overview
========
CMSIS-Driver defines generic peripheral driver interfaces for middleware making it reusable across a wide 
range of supported microcontroller devices. The API connects microcontroller peripherals with middleware 
that implements for example communication stacks, file systems, or graphic user interfaces. 
More information and usage method please refer to http://www.keil.com/pack/doc/cmsis/Driver/html/index.html.

The cmsis_uart_interrupt_transfer example shows how to use uart cmsis driver in interrupt way:

In this example, one uart instance connect to PC through uart, the board will
send back all characters that PC send to the board.

Note: The example echo every 8 characters, so input 8 characters every time.

Toolchain supported
===================
- IAR embedded Workbench  9.20.1
- Keil MDK  5.34
- GCC ARM Embedded  10.2.1
- MCUXpresso  11.4.1

Hardware requirements
=====================
- Mini USB cable
- LPCXpresso55S36 board
- Personal Computer

Board settings
==============

Prepare the Demo
================
1.  Connect a mini USB cable between the PC host and the LPC-Link USB port (J1) on the board.
2.  Open a serial terminal on PC for OpenSDA serial device with these 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
================
The following message shows in the terminal if the example runs successfully.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
USART CMSIS interrupt example
Board receives 8 characters then sends them out
Now please input:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

When you input 8 characters, system will echo it by USART and them would be seen on the OpenSDA terminal.
