PiDraw.cpp

//https://aleksandarhaber.com/incremental-rotary-encoders-with-raspberry-pi-lpd3806-600bm/
/*This project depends on the now depreciated wiring pi project
 * wget https://project-downloads.drogon.net/wiringpi-latest.deb
 * or a working version is also saved the the nanocluster server
 * g++ -Wall -o "%e" "%f" -lwiringPi -lwiringPiDev
 * */
#include <wiringPi.h>
#include <string>
#include <iostream>

using namespace std;
long encoder0;
long encoder1;

int stateA=0;
int stateB=0;
int angle0=0;
int angle1=0;
int OldAngle0=0;
int OldAngle1=0;

//File dataFile;
string dataString = "";

//hardware IO
//may require "gpio mode <pin> in"
/*Encoders*/
int wireA=0;  //BCM 17
int wireB=2;  //BCM 27
int wireC=12; //MOSI
int wireD=13; //MISO
/*Buttons*/
const int buttonAB = 7;  //GPIO7 A-B-encoder pin7 "gpio mode 7 in"
const int buttonCD = 21; //GPIO21 (SCLK) C-D encoder "gpio mode 21 in"


 void A();
 void B();
 void C();
 void D();

 void setup();     //sets up hardware may do all setup including fileIO in teh future
 void resetImg();  //sets data in svg poly line to zero

int main(){
setup();

while(1){
angle0=encoder0;
angle1=encoder1;
        if (digitalRead(buttonAB) == LOW) {
            cout << "Deleting image data\n";
           dataString="";
        delay(100);
        }
        if (digitalRead(buttonCD) == LOW) {
            cout << dataString <<"\n";
        delay(100);
        }
if (angle0==OldAngle0 && angle1==OldAngle1){
     ; //dont do shit if its not changing
}else{
     dataString += ", ";
     dataString +=  to_string(angle0);
     dataString += ", ";
     dataString += to_string(angle1);

     OldAngle0=angle0;
     OldAngle1=angle1;
     cout<<"Angle is:"<<angle0 <<"\t" << angle1 <<endl;

     delay(100);  //read less
     }
}

return 0;
}

void resetImg(){

    }

void setup(){

        wiringPiSetup();
        //isr is an interupt signal, should respond well to random IO
        wiringPiISR(wireA, INT_EDGE_BOTH,&A);
        wiringPiISR(wireB, INT_EDGE_BOTH,&B);
        wiringPiISR(wireC, INT_EDGE_BOTH,&C);
        wiringPiISR(wireD, INT_EDGE_BOTH,&D);

        pinMode(buttonAB, INPUT);
        pinMode(buttonCD, INPUT);
     }

void A(){
    if (stateA==stateB){
        encoder0++;
    }
    stateA=digitalRead(wireA);
    return;
}

void B(){
    if (stateA==stateB){
        encoder0--;
    }
    stateB=digitalRead(wireB);
    return;
}

void C(){
    if (stateA==stateB){
        encoder1++;
    }
    stateA=digitalRead(wireA);
    return;
}

void D(){
    if (stateA==stateB){
        encoder1--;
    }
    stateB=digitalRead(wireB);
    return;
}