#include <SPI.h>

int misoPin = 50;
int mosiPin = 51;
int clkPin = 52;
int csPin = 53;
int clockRate = 1000000;    // between 500kHz and 10 MHz

// Word structure:  2-byte words, 16 bits.
// Clock Priority = Idle Low
// Clock Phase =    first Edge
// WHILE LISTENING TO RESPONSES FROM SENSORS, HOST SHOULD WRITE OUT A 0x0001 TO MOSI LINES TO AVOID ERRORS



// FUNCTION: Prints a byte in binary with all leading 0's
void printBin(byte aByte) {
    for (int8_t aBit = 7; aBit >= 0; aBit--)
        Serial.write(bitRead(aByte, aBit) ? '1' : '0');
}


// FUNCTION: Sends a sample command to the SynTouch NumaTac sensors for DC Pressure.
int samplePDC()
{
    // SPI interfacing
    SPI.beginTransaction(SPISettings(clockRate, MSBFIRST, SPI_MODE0));  // Open up Arduino SPI channel

    digitalWrite(csPin, LOW); // Open comms with NT sensor
    SPI.transfer(0b10000011); // Sample DC Pressure Command (1st Byte)
    SPI.transfer(0x01);       // Sample DC Pressure Command (2nd Byte) [Ignored by NumaTac]

    digitalWrite(csPin, HIGH);// Close comms with NT sensor
    delayMicroseconds(100);   // Mandatory delay; Need minimum of 50 us before can read data from NumaTacs

    digitalWrite(csPin, LOW); // Open comms with NT sensor  

    byte reading1 = SPI.transfer(0x01); // Send a dummy 0x01 while reading the SPI buffer.
    byte reading2 = SPI.transfer(0x01); // Send a dummy 0x01 while reading the SPI buffer.

    digitalWrite(csPin, HIGH);// Close coms with NT sensor

    SPI.endTransaction();                                               // Close Arduino SPI channel
    int byteHandler = 0x0000;
    byteHandler = ((reading1 >> 1) << 5) + (reading2 >> 3);
   
    return byteHandler;
}


// FUNCTION: Sends a sample command to the SynTouch NumaTac sensors for AC Pressure.
int samplePAC()
{
    // SPI interfacing
    SPI.beginTransaction(SPISettings(clockRate, MSBFIRST, SPI_MODE0));  // Open up Arduino SPI channel

    digitalWrite(csPin, LOW); // Open comms with NT sensor
    SPI.transfer(0b10000000); // Sample AC Pressure Command (1st Byte)
    SPI.transfer(0x01);       // Sample AC Pressure Command (2nd Byte) [Ignored by NumaTac]

    digitalWrite(csPin, HIGH);// Close comms with NT sensor
    delayMicroseconds(100);    // Mandatory delay; Need minimum of 50 us before can read data from NumaTacs

    digitalWrite(csPin, LOW); // Open comms with NT sensor  

    byte reading1 = SPI.transfer(0x01); // Send a dummy 0x01 while reading the SPI buffer.
    byte reading2 = SPI.transfer(0x01); // Send a dummy 0x01 while reading the SPI buffer.

    digitalWrite(csPin, HIGH);// Close coms with NT sensor

    SPI.endTransaction();                                               // Close Arduino SPI channel
    int byteHandler = 0x0000;
    byteHandler = ((reading1 >> 1) << 5) + (reading2 >> 3);
  
    return byteHandler;
}