Error Compiling for board Arduino Uno

[andrewmacnicol]

I am trying to use both the Servo and RadioHead libraries to remotely control a Servo with a joystick. Initially my code was working, but at some point I must have changed something and now it is all broken. I have tried unistalling and re-installing the IDE as well as the RH library. I have tried plugging it into different ports on my computer, different computers, different Arduino, nothing seems to make a difference.

I have literally tried uploading a code that is simply #include <RH_ASK.h> and #inlude <Servo.h> along with blank setup and loop functions and I am having the same problem. When I try to include them seperately it works, but when I try to put them in the same code I keep getting the same error:

Arduino: 1.8.13 (Mac OS X), Board: "Arduino Uno"

libraries/RadioHead/RH_ASK.cpp.o (symbol from plugin): In function RH_ASK::maxMessageLength()': (.text+0x0): multiple definition of __vector_11'
libraries/Servo/avr/Servo.cpp.o (symbol from plugin):(.text+0x0): first defined here
collect2: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino Uno.

Any help would be greatly appreciated. I am trying to teach my students the fun of Arduino in a club, but I must admit this has stumped me for quite a while.

sketch_mar23b.ino (170 Bytes)

[chall3ng3r]

This looks like conflict in defines in libraries. One variable is defined multiple times.

You can modify one of these libraries, I'd recommend RH lib and find and replace "__vector_11" with something else, for example "__rh_vector_11".

Now try compiling again, and see if it fixed the error.

[david_2018]

The error message is rather cryptic, the problem is that the Servo and RadioHead libraries both use hardware timer1. If you look at the RH_ASK.cpp file in the RadioHead library, you will find the following (I added the line numbers to the left of each line):

 24 
 25 // RH_ASK on Arduino uses Timer 1 to generate interrupts 8 times per bit interval
 26 // Define RH_ASK_ARDUINO_USE_TIMER2 if you want to use Timer 2 instead of Timer 1 on Arduino
 27 // You may need this to work around other librraies that insist on using timer 1
 28 // Should be moved to header file
 29 //#define RH_ASK_ARDUINO_USE_TIMER2
 30

Uncomment the #define on line 29 and the error should go away.

[andrewmacnicol]

david_2018, this worked thank you so much!

[groundFungus]

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