//This code was written to be easy to understand.
//Code efficiency was not considered.
//Modify this code as you see fit.
//This code will output data to the Arduino serial monitor.
//Type commands into the Arduino serial monitor to control the pH circuit.
//This code was written in the Arduino 1.6.5 IDE
//An Arduino Mega was used to test this code.
String inputstring = ""; //a string to hold incoming data from the PC
String sensorstring = ""; //a string to hold the data from the Atlas Scientific product
boolean input_string_complete = false; //have we received all the data from the PC
boolean sensor_string_complete = false; //have we received all the data from the Atlas Scientific product
float pH; //used to hold a floating point number that is the pH
void setup() { //set up the hardware
Serial.begin(9600); //set baud rate for the hardware serial port_0 to 9600
Serial3.begin(9600); //set baud rate for software serial port_3 to 9600
inputstring.reserve(10); //set aside some bytes for receiving data from the PC
sensorstring.reserve(30); //set aside some bytes for receiving data from Atlas Scientific product
}
void serialEvent() { //if the hardware serial port_0 receives a char
inputstring = Serial.readStringUntil(13); //read the string until we see a <CR>
input_string_complete = true; //set the flag used to tell if we have received a completed string from the PC
}
void serialEvent3() { //if the hardware serial port_3 receives a char
sensorstring = Serial3.readStringUntil(13); //read the string until we see a <CR>
sensor_string_complete = true; //set the flag used to tell if we have received a completed string from the PC
}
void loop() { //here we go...
if (input_string_complete == true) { //if a string from the PC has been received in its entirety
Serial3.print(inputstring); //send that string to the Atlas Scientific product
Serial3.print('\r'); //add a <CR> to the end of the string
inputstring = ""; //clear the string
input_string_complete = false; //reset the flag used to tell if we have received a completed string from the PC
}
if (sensor_string_complete == true) { //if a string from the Atlas Scientific product has been received in its entirety
Serial.println(sensorstring); //send that string to the PC's serial monitor
if (isdigit(sensorstring[0])) { //if the first character in the string is a digit
pH = sensorstring.toFloat(); //convert the string to a floating point number so it can be evaluated by the Arduino
if (pH >= 7.0) { //if the pH is greater than or equal to 7.0
Serial.println("high"); //print "high" this is demonstrating that the Arduino is evaluating the pH as a number and not as a string
}
if (pH <= 6.99) { //if the pH is less than or equal to 6.99
Serial.println("low"); //print "low" this is demonstrating that the Arduino is evaluating the pH as a number and not as a string
}
}
}
sensorstring = ""; //clear the string:
sensor_string_complete = false; //reset the flag used to tell if we have received a completed string from the Atlas Scientific product
}
