Miniph pH interface

MinipH is a very cost effective solution for adding pH sensing capability to any project. MinipH uses a popular and proven 12 bit ADC that is very easy to work with, precise, and reliable, taking measurements is a snap. This makes it an ideal addition to any electronic tool box, especially those that need water quality sensors! Designed to be easily integrated with projects using either a breadboard(standard .1" header) or even use a Seeed Grove connector! This is an open source hardware project and all files can be found on MinipH's Project page!

Various Info

• Version 4.0 of Hardware
• Full pH range .1 - 14 (.01 precision, though probes are only good for .1)
• Wide range of VIN inputs (2.7 to 5.5V) works with RaspI's
• Easy to use 12bit ADC

Example Arduino code

Very simple code to read ADC and assemble 12bit number! pH can then be calculated just like with other projects! See MinipH's Project page for full code examples as well!

#include 
#include 
#include

#define MAX_LENGTH 18
#define VERSION 0x0001

uint8_t pHi2cAddress = 0x4D;    // MCP3221 A5 in Dec 77 A0 = 72 A7 = 79)

void setup()
{
    //The library assume you will initialize the wire library mine as well do this here
    Wire.begin();
    //initialize and run anything that needs to be performed prior to the main loop executing for the first time
    Serial.begin(115200);
    Serial.println("MINIPH Library Usage Example");
}

void loop()
{
    int pHtemp = miniph.calcRollingAVG();
    int pHtemp2 = miniph.readI2CADC();

    if (Serial.available() > 0)
    {
    processIncomingByte(Serial.read());
    }

    Serial.println(pHtemp);

    delay(500);
}

void processIncomingByte(const char inByte)
{
    static unsigned int numChars = 0;
    switch (inByte)
    {
        case '\n':   // end of text      
    // terminator reached! process input_line here ...
    numChars = 0;
    processMessage(messageIn);
    break;

        case '\r':   // discard carriage return
    break;

        default:
    // keep adding if not full ... allow for terminating null byte
    if (numChars < (MAX_LENGTH - 1))
        messageIn += inByte;
    numChars++;
    break;

}  // end of switch

} // end of processIncomingByte

void processMessage(String msg)
{
Serial.println(msg);
if (msg.startsWith("C"))
{
    //we received a calibration string lets rip it apart to see what to do
    char whichType, whatCal;
    whichType = msg.charAt(1);
    whatCal = msg.charAt(2);
    String tempStringtoInt = "";

    int nDex = 3;
    //Serial.println(msg);
    while (msg[nDex] != ',' && nDex < MAX_LENGTH)
    {
        //Serial.println(msg[nDex]);
        tempStringtoInt += msg[nDex];
        nDex++;
    }
    int calMapReference = tempStringtoInt.toInt();

    switch (whichType)
    {
        case 'E':               
            //now lets check which cal we want to run in the eC group
            //We want to calibrate our low
            if (whatCal == 'L')
            {
                //miniec.calibrateeCLow(miniec.calcRollingAVG(),(long)tempStringtoInt.toInt());
            }
            else if (whatCal == 'H') //or our high
            {
                //miniec.calibrateeCHigh(miniec.calcRollingAVG(), (long)tempStringtoInt.toInt());
            }
        break;

        case 'P':
            if (whatCal == '7')
            {
                miniph.calibratepH7(miniph.calcRollingAVG());
            }
            else if (whatCal == '4')
            {
                miniph.calibratepH4(miniph.calcRollingAVG());
            }
            else if (whatCal == '10')
            {
                miniph.calibratepH10(miniph.calcRollingAVG());
            }
        break;

        default:
            break;

    }

}
if (msg.startsWith("R"))
{
    Serial.print("pH: ");
    Serial.print(miniph.calcpH(miniph.calcRollingAVG()));
    Serial.print(" | ");
    Serial.println("eC: ");
    //Serial.println(miniec.mapeC(miniec.calcRollingAVG()));
}
if (msg.startsWith("S"))
{
    //Stop
    //do whatever you want here to stop or what and S command might be
}

if (msg.startsWith("I"))
{
    //Lets read in our parameters and spit out the info! 
    //eeprom_read_block(¶ms, (void *)0, sizeof(params));
    sendSerialInfo('I');
}
if (msg.startsWith("X"))
{
    //restore to default settings
    Serial.println("Reseting to default settings");
    //miniec.reset_eCParams();
    miniph.reset_pHParams();
}
//clear out our message buffer
messageIn = "";
}

void sendSerialInfo(char charStatusInfo)
{

Serial.print("MiniLib pH and eC Example: Firmware Ver ");
Serial.println(VERSION);
Serial.print("pH 7 cal: ");
Serial.print(miniph._pHParams.pH7Cal);
Serial.print(" | ");
Serial.print("pH 4 cal: ");
Serial.print(miniph._pHParams.pH4Cal);
Serial.print(" | ");
Serial.print("pH 10 cal: ");
Serial.print(miniph._pHParams.pH10Cal);
Serial.print(" | ");
Serial.print("pH probe slope: ");
Serial.println(miniph._pHParams.pHStep);

Serial.print("eC Low cal: ");
//Serial.print(miniec._eCParams.eCLow);
Serial.print(" | ");
Serial.print("eC Low Ref: ");
//Serial.print(miniec._eCParams.eCRefLow);
Serial.print(" | ");
Serial.print("eC High cal: ");
//Serial.print(miniec._eCParams.eCHigh);
Serial.print(" | ");
Serial.println("eC High Ref: ");
//Serial.println(miniec._eCParams.eCRefHigh);

}