I have fair experience with C/C++ so I decided to have a go at writing my first simple Arduino library. I wrote the code which seems to be fine to me except that it keeps complaining about the header file not found during compilation:

/home/me/sketchbook/libraries/SegDisplay/SegDisplay.cpp:1:24: fatal error: SegDispaly.h: No such file or directory
 #include "SegDispaly.h"
compilation terminated.

I have the library located in my sketch folder under the name "SegDisplay":

└── SegDisplay
    ├── examples
    ├── keywords.txt
    ├── README.md
    ├── SegDisplay.cpp
    └── SegDisplay.h

and here's the code:


#ifndef _SEVEN_SEG_H_
#define _SEVEN_SEG_H_

#include <math.h>

#if defined(ARDUINO) && (ARDUINO >= 100)
#include <Arduino.h>
#include <WProgram.h>

class SegDisplay
    SegDisplay (int clockPin, int latchPin, int dataPin, int digitPins[4]);
    void display (double value);

    const int digitPins[4];
    const int clockPin;
    const int latchPin;
    const int dataPin;
    const byte digit[10] = //seven segment digits in bits
        B00111111, //0
        B00000110, //1
        B01011011, //2
        B01001111, //3
        B01100110, //4
        B01101101, //5
        B01111101, //6
        B00000111, //7
        B01111111, //8
        B01101111  //9
    int digitBuffer[4];

    void setRegisterData (byte data);
    void clearRegister();
    void clearDisplay();
    void updateDisplay();



#include "SegDispaly.h"

SegDisplay::SegDisplay (int a, int b, int c, int d[4]):
    clockPin (a), latchPin (b), dataPin (c), digitPins (d), digitBuffer ({0})
    for (int i = 0; i < 4; i++)
        pinMode (digitPins[i], OUTPUT);
        digitalWrite (digitPins[i], HIGH);
    pinMode (latchPin, OUTPUT);
    pinMode (clockPin, OUTPUT);
    pinMode (dataPin, OUTPUT);  

void SegDispaly::setRegisterData (byte data)
    digitalWrite (latchPin, LOW);  
    shiftOut (dataPin, clockPin, MSBFIRST, data);
    digitalWrite (latchPin, HIGH);

void SegDispaly::clearRegister()
    setRegisterData (B00000000);

void SegDispaly::clearDisplay()
    // deactivate transistors
    for (int n = 0; n < 4; n++) digitalWrite (digitPins[n], HIGH);

//writes the temperature on display
void SegDispaly::updateDisplay()
    byte outByte;
    // dispaly digits
    for (int i = 0; i < 4; i++)

        // enable nth cell cathode (transistor)
        digitalWrite (digitPins[i], LOW); 

        // output nth digit on display
        if (i == 1)
            //print the decimal point on the 2nd digit
            outByte = digit[digitBuffer[i]] | B10000000;
        else outByte = digit[digitBuffer[i]];
        setRegisterData (outByte);

        //delayMicroseconds (500);
        delay (5);

        //Serial.print (outByte, BIN);
        //if (i == 3)
        //  Serial.println (".");
        //else Serial.print (", ");

void SegDispaly::display (double value)
    int n = int (value * 100);
    digitBuffer[0] = n / 1000;
    digitBuffer[1] = (n % 1000) / 100;
    digitBuffer[2] = (n % 100) / 10;
    digitBuffer[3] = (n % 100) % 10;

My target AVR is Arduino Uno R3, the code used to work fine in a sketch before I decided to create a library out of it. Any help would be greatly appreciated. thanks in advance.


You spelled the header filename wrong:

#include "SegDispaly.h"

should be:

#include "SegDisplay.h"

You have also made the same mistake in the class name multiple places in SegDisplay.cpp.

| improve this answer | |
  • you know I checked the spelling of SegDisplay several times and couldn't spot it for some reason, I must be going blind. Thanks – user7342539 Aug 7 '17 at 22:32

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