SPI demo example

Description of example project
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Send a 2 periodic (1s) messages with different frame lengths via SPI.

Hardware Setup
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XMC4500 CPU Board
Rx Pin : 2.15 , Tx Pin : 2.12 , SELO Pin : 0.6 , CLOCK Pin : 0.11

How to test the application
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a. Import the project
b. Compile and flash the application onto the device
c. Run the application. 
d. Configure a slave to receive the signals or see the signals in an oscilloscope.