PComp Lab: Wireless Serial/SPI Communication

So this week has been another week of despair, as as soon as I fixed my first issue with my midterm project, we have another going on. I might need to play around with things for a bit. But as of this writing I am meeting up with my partner and having a jam session to hammer this out. This is a very long post– but I wanted to be as detailed as possible for troubleshooting purposes.

At any case, to the lab!

So I had thought to try it with my own Wi-Fi transciever, the ESP8266.

I searched a datasheet and lucky me someone even made a Fritzing schematic for it! But here ‘s the rub, as you will see.


So as you see from the schematic and the actual image– it’s already got pins! So I’m not sure how to address that on the breadboard. But luckily the Equipment Room has a Bluefruit EZ-Link available so I just got that bad boy and set it up!


Hooking up to the Bluetooth went without a hitch but…then I got to Arduino IDE and here comes the errors!¬†Using the code we worked on in class for the sake of ease, added the extra pots and labeled them all nice, the sketch was verified but… was getting a generic “An error occurred while uploading the sketch”. Little bit of Google-Fu, and I found a fix. Okay, tried that, it uploaded fine… but then I started getting the “avrdude: ser_open(): can’t open device “\\.\COM6”: Access is denied.” Error. Check my browser, no p5 tabs open, check the serialport reader app, it’s not even open, so then…why is my arduino not reading?

I managed to find another fix, albeit a temporary one. Because even when I upload, my sensor readings won’t even ¬†show up on the serial monitor. And sometimes when opening the serial monitor, I get a “COM6 is busy” message, despite having nothing else related to serial open. ¬†This was another error I got on another attempt:

An error occurred while uploading the sketch
avrdude: ser_open(): can’t open device “\\.\COM6”: Access is denied.
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
Exception in thread “Thread-53” java.util.ConcurrentModificationException
at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:966)
at java.util.LinkedList$ListItr.next(LinkedList.java:888)
at processing.app.BaseNoGui.populateImportToLibraryTable(BaseNoGui.java:968)
at processing.app.BaseNoGui.onBoardOrPortChange(BaseNoGui.java:831)
at processing.app.Base.onBoardOrPortChange(Base.java:1249)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2439)
at java.lang.Thread.run(Thread.java:745)

After much suffering, I decided to work backwards. Maybe there was sensor issue– hence why the monitor wasn’t working. I was wrong! Set it up just to read the pots and works just fine!

Then I  tried for the shits and giggles the p5 sketch. I reupload the Arduino code (this time with no errors!) and ad my port to the p5 sketch. As suspected, nothing.  So now I am at a loss at what to do!


So…instead of frustrating myself further, I tried a second lab, with slightly more success?
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Set up the board and put in the code… only to just have a tone. even bumped up the delays to see if it’s just my hearing, alas, the same monotone beep! I thought to try out another resistor, wondering if perhaps the 100 ohm resistor should have been a 10 ohm, since they look similar in name and color, still nothing. Double-checked my wiring and followed the Frizting example to a T. Triple checked, even as seen from above. ¬†Followed the code all the same, the only change is in the delays, and yet…having problems.


I have no idea what to do.

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