Arduino Class Redefinition Error - c++

Question

In my Arduino IDE I have set up a program that runs eight LEDs through a shift register and now am trying to make a class to control the shift register. So far I have created the file and created a constructor with a few functions for the class, but when I try to verify the code the IDE says that I am redefining the class shiftreg here is the error message:
In file included from Lab9_step3.cpp:97:
shiftreg.h:2: error: redefinition of 'class shiftreg'
shiftreg.h:3: error: previous definition of 'class shiftreg'
and my code for lab_9 is:
/* ---------------------------------------------------------
* | Arduino Experimentation Kit Example Code |
* | CIRC-05 .: 8 More LEDs :. (74HC595 Shift Register) |
* ---------------------------------------------------------
*
* We have already controlled 8 LEDs however this does it in a slightly
* different manner. Rather than using 8 pins we will use just three
* and an additional chip.
*
*
*/
#include "shiftreg.h"
//Pin Definitions
//Pin Definitions
//The 74HC595 uses a serial communication
//link which has three pins
shiftreg a(2, 3, 4);
int sensorPin = 0; // select the input pin for the potentiometer
int sensorValue = 0; // variable to store the value coming from the sensor
/*
* setup() - this function runs once when you turn your Arduino on
* We set the three control pins to outputs
*/
void setup()
{
a.pinmode();
}
/*
* loop() - this function will start after setup finishes and then repeat
* we set which LEDs we want on then call a routine which sends the states to the 74HC595
*/
void loop() // run over and over again
{
for(int i = 0; i < 256; i++){
a.update(i);
// read the value from the sensor:
sensorValue = analogRead(sensorPin);
delay(sensorValue);
}
}
/******************************
/*
* updateLEDsLong() - sends the LED states set in ledStates to the 74HC595
* sequence. Same as updateLEDs except the shifting out is done in software
* so you can see what is happening.
*/
// void updateLEDsLong(int value){
// digitalWrite(latch, LOW); //Pulls the chips latch low
// for(int i = 0; i < 8; i++){ //Will repeat 8 times (once for each bit)
// int bit = value & B10000000; //We use a "bitmask" to select only the eighth
// //bit in our number (the one we are addressing this time thro
// //ugh
// value = value << 1; //we move our number up one bit value so next time bit 7 will
// // be
// //bit 8 and we will do our math on it
// if(bit == 128){digitalWrite(data, HIGH);} //if bit 8 is set then set our data pin high
// else{digitalWrite(data, LOW);} //if bit 8 is unset then set the data pin low
// digitalWrite(clock, HIGH); //the next three lines pulse the clock pin
// delay(1);
// digitalWrite(clock, LOW);
// }
// digitalWrite(latch, HIGH); //pulls the latch high shifting our data into being displayed
// }
//
//
// //These are used in the bitwise math that we use to change individual LEDs
// //For more details http://en.wikipedia.org/wiki/Bitwise_operation
// int bits[] = {B00000001, B00000010, B00000100, B00001000, B00010000, B00100000, B01000000, B10000000};
// int masks[] = {B11111110, B11111101, B11111011, B11110111, B11101111, B11011111, B10111111, B01111111};
// /*
// * changeLED(int led, int state) - changes an individual LED
// * LEDs are 0 to 7 and state is either 0 - OFF or 1 - ON
// */
// void changeLED(int led, int state){
// ledState = ledState & masks[led]; //clears ledState of the bit we are addressing
// if(state == ON){ledState = ledState | bits[led];} //if the bit is on we will add it to le
// //dState
// updateLEDs(ledState); //send the new LED state to the shift register
// }
// **********************************/
and my code for shiftreg.h is:
/*Shift Register
*/ (Error occurs here)
class shiftreg (and here)
{
private:
//Pin Definitions
//Pin Definitions
//The 74HC595 uses a serial communication
//link which has three pins
int data;
int clock;
int latch;
public:
shiftreg (int _data, int _clock, int _latch);
void update(int value);
void pinmode();
};
and my code for shiftreg.cpp is:
#include "shiftreg.h"
/*shiftreg constructor:
*/
shiftreg::shiftreg (int _data, int _clock, int _latch)
{
data = _data;
clock = _clock;
latch = _latch;
//Used for single LED manipulation
int ledState = 0;
const int ON = HIGH;
const int OFF = LOW;
}
/*
* updateLEDs() - sends the LED states set in ledStates to the 74HC595
* sequence
*/
void shiftreg::update(int value)
{
digitalWrite(latch, LOW); //Pulls the chips latch low
shiftOut(data, clock, MSBFIRST, value); //Shifts out the 8 bits to the shift register
digitalWrite(latch, HIGH); //Pulls the latch high displaying the data
}
/*
*/
void shiftreg::pinmode()
{
pinMode(data, OUTPUT);
pinMode(clock, OUTPUT);
pinMode(latch, OUTPUT);
}
Thanks for the help!

Answer 1

According to the error message you're including shiftreg.h on line 97 of Lab9_step3.cpp. What's on the 96 lines above that? The error probably lies somewhere in there.
If I had to guess, I'd say you're, either directly, or indirectly, including shiftreg.h twice (or more) in Lab9_step3.cpp, and the error's occurring because you don't have include guards in your header file.
Try adding the following to shiftreg.h
#ifndef SHIFTREG_H
#define SHIFTREG_H
class shiftreg
{
// ...
};
#endif