Error compiling for board SparkFun Pro Micro

Hey, I'm pretty new to Arduino and I am currently making a macro pad with 5 switches and a rotary encoder. I've downloaded and installed the SparkFun Pro Micro and the first time I've tried to verify and upload it says this:

< #include <HID-Project.h>
#include <HID-Settings.h>
#include <Encoder.h>
#include <Bounce2.h>
#include <Keyboard.h>

//Set up the button grid
const int numButtons = 5;
const int buttonPins[numButtons] = {9,8,7,6,5}; //defining the pins in an order from right to left
int state = 0; //Set the current state
//Set up all the buttons as bounce objects
Bounce buttons[x] = {Bounce(buttonPins[0],10),Bounce(buttonPins[1],10),Bounce(buttonPins[2],10),Bounce(buttonPins[3],10),Bounce(buttonPins[4],10)};

//Set up the encoder
const int encoderButtonPin = 10;
Encoder volumeKnob(14,15); //Set up the encoder as an Encoder object
Bounce encoderButton = Bounce(encoderButtonPin,10); //Set up to the encoder button as a Bounce object
int timeLimit = 500; //Cut off time for play/pause or skip

void setup() {
Keyboard.begin(); //Start the Keyboard object

for(int i = 0; i < numButtons; i++){
pinMode(buttonPins[i], INPUT_PULLUP);

pinMode(encoderButtonPin, INPUT_PULLUP);
long positionLeft = -999;
void loop() {
//check all buttons
for(int j = 0; j < numButtons; j++){

//use the current state and the button number to find the command needed and send it.
switch (state) {
case 0: //Layout 1
switch (j) {

case 0: //F6;
case 1: //;
case 2: //;
case 3: //;
case 4: //;

//encoder play pause
if(encoderButton.update()) {
if(encoderButton.fallingEdge()) {
int fall = millis();
int rise = millis();
Serial.println(rise - fall);
if(rise - fall > timeLimit){;
} else {;
long positionLeft = -9;
long positionRight = -9;

//encoder volume changing
long newLeft;
newLeft =;

if(newLeft != positionLeft){
if((newLeft - positionLeft) > 0) {
Serial.println("volume up");;
} else {
Serial.println("volume down");;
positionLeft = newLeft;
} >

Hi @pyrothmatic.

I'm going to ask you to post some additional information that might help us to identify the problem.

Please do this:

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  2. Open a forum reply here by clicking the Reply button.
  3. Click the </> icon on the post composer toolbar. This will add the forum's code block markup (```) to your reply to make sure the error messages are correctly formatted.
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  6. Click the Reply button to post the output.
Arduino: 1.8.13 (Windows 10), Board: "SparkFun Pro Micro, ATmega32U4 (3.3V, 8 MHz)"

In file included from c:\users\190240\documents\arduino\libraries\hid-project\src\hid-apis\KeyboardAPI.h:29:0,

                 from c:\users\190240\documents\arduino\libraries\hid-project\src\hid-apis\defaultkeyboardapi.h:27,

                 from C:\Users\190240\Documents\Arduino\libraries\HID-Project\src/SingleReport/BootKeyboard.h:30,

                 from C:\Users\190240\Documents\Arduino\libraries\HID-Project\src/HID-Project.h:50,

                 from C:\Users\190240\Desktop\Electronic Tech Macropad\Macropad_Code\Macropad_Code.ino:1:

c:\users\190240\documents\arduino\libraries\hid-project\src\keyboardlayouts\improvedkeylayouts.h:54:21: note: #pragma message: Using default ASCII layout for keyboard modules

     #pragma message "Using default ASCII layout for keyboard modules"


In file included from C:\Users\190240\Desktop\Electronic Tech Macropad\Macropad_Code\Macropad_Code.ino:5:0:

C:\Program Files (x86)\Arduino\libraries\Keyboard\src/Keyboard.h:95:7: error: redefinition of 'class Keyboard_'

 class Keyboard_ : public Print


In file included from C:\Users\190240\Documents\Arduino\libraries\HID-Project\src/HID-Project.h:51:0,

                 from C:\Users\190240\Desktop\Electronic Tech Macropad\Macropad_Code\Macropad_Code.ino:1:

C:\Users\190240\Documents\Arduino\libraries\HID-Project\src/MultiReport/ImprovedKeyboard.h:33:7: note: previous definition of 'class Keyboard_'

 class Keyboard_ : public DefaultKeyboardAPI


exit status 1

Error compiling for board SparkFun Pro Micro.

This is the error code

It looks like the HID-Project library and the Keyboard library you are using are incompatible with each other. If I understand correctly, the HID-Project library's "ImprovedKeyboard" is a replacement for the Keyboard library, so it makes no sense at all to try to use both at the same time. Please study the HID-Project library's extensive documentation to learn how to use it correctly:

Alternatively, you might find it much easier to just use the standard Keyboard library alone. That library might well meet all your needs. The Keyboard library's documentation is here:

@pyrothmatic, your topic has been moved to a more suitable location on the forum.

ATmega32U4 (3.3V, 8 MHz)"

Are you sure the Pro Micro is the 3.3V variant? The 5 V/16 MHz version is much more common.

I changed that by mistake it is meant to be 5v, thanks for reminding me.

Thank you so much for your help, it worked after I deleted the keyboard library.

You're welcome. I'm glad to hear it's working now. Enjoy!

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