#include <SPI.h>
int clock = 9;
void resetsensor() //this function keeps the sketch a little shorter
{
SPI.setDataMode(SPI_MODE0);
SPI.transfer(0x15);
SPI.transfer(0x55);
SPI.transfer(0x40);
}
void setup() {
Serial.begin(9600);
SPI.begin(); //see SPI library details on arduino.cc for details
SPI.setBitOrder(MSBFIRST);
SPI.setClockDivider(SPI_CLOCK_DIV32); //divide 16 MHz to communicate on 500 kHz
pinMode(clock, OUTPUT);
delay(100);
}
void loop()
{
TCCR1B = (TCCR1B & 0xF8) | 1 ; //generates the MCKL signal
analogWrite (clock, 128) ;
resetsensor();//resets the sensor - caution: afterwards mode = SPI_MODE0!
//Calibration word 1
unsigned int word1 = 0;
unsigned int word11 = 0;
SPI.transfer(0x1D); //send first byte of command to get calibration word 1
SPI.transfer(0x50); //send second byte of command to get calibration word 1
SPI.setDataMode(SPI_MODE1); //change mode in order to listen
word1 = SPI.transfer(0x00); //send dummy byte to read first byte of word
word1 = word1 << 8; //shift returned byte
word11 = SPI.transfer(0x00); //send dummy byte to read second byte of word
word1 = word1 | word11; //combine first and second byte of word
resetsensor();//resets the sensor
//Calibration word 2; see comments on calibration word 1
unsigned int word2 = 0;
byte word22 = 0;
SPI.transfer(0x1D);
SPI.transfer(0x60);
SPI.setDataMode(SPI_MODE1);
word2 = SPI.transfer(0x00);
word2 = word2 <<8;
word22 = SPI.transfer(0x00);
word2 = word2 | word22;
resetsensor();//resets the sensor
//Calibration word 3; see comments on calibration word 1
unsigned int word3 = 0;
byte word33 = 0;
SPI.transfer(0x1D);
SPI.transfer(0x90);
SPI.setDataMode(SPI_MODE1);
word3 = SPI.transfer(0x00);
word3 = word3 <<8;
word33 = SPI.transfer(0x00);
word3 = word3 | word33;
resetsensor();//resets the sensor
//Calibration word 4; see comments on calibration word 1
unsigned int word4 = 0;
byte word44 = 0;
SPI.transfer(0x1D);
SPI.transfer(0xA0);
SPI.setDataMode(SPI_MODE1);
word4 = SPI.transfer(0x00);
word4 = word4 <<8;
word44 = SPI.transfer(0x00);
word4 = word4 | word44;
long c1 = word1 >> 1;
long c2 = ((word3 & 0x3F) << 6) | ((word4 & 0x3F));
long c3 = (word4 >> 6) ;
long c4 = (word3 >> 6);
long c5 = (word2 >> 6) | ((word1 & 0x1) << 10);
long c6 = word2 & 0x3F;
resetsensor();//resets the sensor
//Temperature:
unsigned int tempMSB = 0; //first byte of value
unsigned int tempLSB = 0; //last byte of value
unsigned int D2 = 0;
SPI.transfer(0x0F); //send first byte of command to get temperature value
SPI.transfer(0x20); //send second byte of command to get temperature value
delay(35); //wait for conversion end
SPI.setDataMode(SPI_MODE1); //change mode in order to listen
tempMSB = SPI.transfer(0x00); //send dummy byte to read first byte of value
tempMSB = tempMSB << 8; //shift first byte
tempLSB = SPI.transfer(0x00); //send dummy byte to read second byte of value
D2 = tempMSB | tempLSB; //combine first and second byte of value
resetsensor();//resets the sensor
//Pressure:
unsigned int presMSB = 0; //first byte of value
unsigned int presLSB =0; //last byte of value
unsigned int D1 = 0;
SPI.transfer(0x0F); //send first byte of command to get pressure value
SPI.transfer(0x40); //send second byte of command to get pressure value
delay(35); //wait for conversion end
SPI.setDataMode(SPI_MODE1); //change mode in order to listen
presMSB = SPI.transfer(0x00); //send dummy byte to read first byte of value
presMSB = presMSB << 8; //shift first byte
presLSB = SPI.transfer(0x00); //send dummy byte to read second byte of value
D1 = presMSB | presLSB;
const long UT1 = (c5 * 8) + 20224;
const long dT =(D2 - UT1);
const long TEMP = 200 + ((dT * (c6 + 50))/1024);
const long OFF = (c2*4) + (((c4 - 512) * dT)/4096);
const long SENS = c1 + ((c3 * dT)/1024) + 24576;
long PCOMP = ((((SENS * (D1 - 7168))/16384)- OFF)/32)+250;
float TEMPREAL = TEMP/10;
Serial.print("pressure = ");
Serial.print(PCOMP);
Serial.println(" mbar");
const long dT2 = dT - ((dT >> 7 * dT >> 7) >> 3);
const float TEMPCOMP = (200 + (dT2*(c6+100) >>11))/10;
Serial.print("temperature = ");
Serial.print(TEMPCOMP);
Serial.println(" °C");
Serial.println("************************************");
delay(1000);
}
i connected
SCLK pin 52
DOUT pin 50
DIN pin 51
MCLK pin 9
Now if you just set the Serial monitor's baud rate to match your Arduino's Serial baud rate you'll likely see normal ASCII characters.
Make sure the sensor is in SPI mode, not I2C mode. See datasheet on proper connections and how the mode is selected.
well that serial baud rate is my bad (sorry, i'm beginner at Arduino) , now it just working fine after some learning about SPI.
So another question the baud rate is set at library code at 115200, if i changed it to 9600 will it make an issue ? because i want to merge it with another sensors which i used 9600 baud rate
KareemWaheed:
So another question the baud rate is set at library code at 115200, if i changed it to 9600 will it make an issue ? because i want to merge it with another sensors which i used 9600 baud rate
Serial communications becomes slower. This may or may not be an issue, depending on what else you intend to do.
