I am working on a project where I use an arduino uno in the loop with a rc receiver feeding information into it, then the uno is sending information into an APM 2.5 autopilot to control a drone.

The first approach i was using involved code that used pulseIn to read the pwm from the receiver and it worked but was very sloppy.

So we switched over to interrupts and I used some example code to read the rc controller and the readings were beautiful.

The next step was I wanted to read multiple channels and be able to control the drone again using my rc controller going through the uno. I found this project and it looked good I just needed to make some small tweaks for my application.

The problem I am having is this uses a library and I have downloaded and installed the proper library, but it's not working. I try to compile and i get " 'PCintPort' has not been declared ". I've also noticed that when I try to put the library in the code with the drop down menu it just puts a blank space in there instead. I tested other libraries and they will put in the lines of code in properly (ex. #include <EEPROM.h>).

So does anyone have any idea what is going on here? I am very confused, I've tried using both the latest stable IDE and the beta. Deleted the library and installed different versions. I'm at a loss.

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  • Hi Nick,

    I just tried on a fresh install of Arduino. I added this version of the library: https://github.com/asheeshr/PinChangeInt by placing it in the Arduino 'libraries' folder. It compiled fine. If you already have a copy of Arduino running when you copy over the library, then restart. If your Arduino installation is seeing the library correctly then you should also see the PinChangeInt examples under File->Examples



    A fork of the PinChangeInt library hosted on Google Code. This is usable in projects across multiple files. - asheeshr/PinChangeInt
    • Thank you for the reply.

      I have been following this procedure to load libraries into my IDE. I've tried many different versions of the IDE also. They came out with a new version of the library yesterday and it didn't work either. Yet my labmate, she is able to compile the code just fine like you and another person on another forum.

      I am thinking that something outside of the IDE is influencing this. I try google search and can't come up with anything so I'm trying every forum related to the items I'm working with.

      So far I've tested this on 4 different computers. Every computer I test it on the library won't reference when I compile. I've tested this on 3 windows 7 computers and an XP.

      • Nick,

        There must be something you are doing. I just tried it on an XP machine and it worked fine.

        What is your 'sketchbook location' under File->Preferences?

        Where did you place the PinChangeInt library?

        Does PinChangeInt show up when you select File->Examples?

        What board are you compiling for?

  • An update and a bump I have found a few people that can compile this code but every computer I try to do this on it will not work. I have done just about everything imaginable to clean up my computer to get rid of anything that might be interfering except a complete wipe since I need an external to back up some things. Anyone know of any known programs that interfere with the Arduino IDE or have been known to if they start to corrupt?

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