Week 26 (Apr. 10, 2019): Programming – Python and Arduino Communication

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The Python code and the Arduino code are able to run successfully on their respective boards, i.e. the Raspberry Pi in the tablet and the Arduino in the pod car. However, the Raspberry Pi is having issues sending data to the Arduino via the XBee RF (radio-frequency) module, specifically the user-input data. Whenever the user inputs the pickup station, destination, and selects a pod car, the Serial Monitor on the Arduino IDE does not show any of the data. Investigating further, we plugged the XBee module into one of our laptops, then opened the XCTU software’s (the software which deals with RF modules) Serial port as well. Now, whenever the user inputs the stations, we can see on the XCTU Serial Monitor that the receiving XBee does get the pickup station, destination, and pod car number, but the three inputs are all found between jumbles of random characters. As displayed in the screenshot of the XCTU software below, if the user inputs pickup station 2, destination station 5, and selects pod car 1, the values 02, 05, and 01 do indeed appear in the Console log; however, there are series of random characters between them.

We are not quite sure how to fix this issue, but we will try to fix it. And even though communication from the Raspberry Pi to the Arduino is not working for now, at least the Arduino can still run on its own.


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