I hope to cover all the questions in order:
- My question is what would be the best way to interface the python application program with the Arduino sketches?
Since the function system () sets the processor to execute a Linux command, it is a good way to interface a python script with the Arduino sketch.
- Would you have any other suggestions to improve the concept?
If you have a serial cable you can program the Galileo using Python (without Arduino IDE at all) and run a your *.py routine. As you might know, the concept is more related to the Linux environment, board pin out, file management and Python skills programming.
- is it possible to write a python script to take the data straight in via SPI and not use an Arduino sketch?
I think it is possible, but you’ll need to program some more settings than the required using an Arduino sketch. For instance, in this link https://learn.sparkfun.com/tutorials/programming-the-pcduino/spi-communications you can find some code for SPI using C++ and Python for a similar board, you can use the same code and adapt it to your needs in the Galileo one.
In this additional link, you can find information about the GPIO Mapping in Galileo Intel Galileo - Programming GPIO From Linux - Malinov Family Web Presence and how the SPI pins are confirgured.
- if I wanted to write the application program in c/c++, would that be possible? Would I have to do it using the IoT dekit? Do you write the c/c++ program in the Eclipse IDE and then load it onto the board like an arduino sketch? Can Arduino sketches interact with c/c++ programs?
Regarding the IoT Dev Kit, we highly recommend you to visit this link https://software.intel.com/en-us/forums/internet-of-things where you can find more resources