Hey
I have the Melexis 90614ACC (That is the 5v version) of the sensor and i tried to read temp data from it using the i2c master library and dave eatons code as follows:
#include <i2cmaster.h>
void setup()
{
Serial.begin(9600);
Serial.println("Hello!");
i2c_init(); //Initialise the i2c bus
Serial.println("Return from i2c_init");
PORTC = (1 << PORTC4) | (1 << PORTC5);//enable pullups
}
void loop()
{
int dev = 0x5A<<1;
int data_low = 0;
int data_high = 0;
int pec = 0;
i2c_start_wait(dev+I2C_WRITE);
i2c_write(0x07);
i2c_rep_start(dev+I2C_READ);
data_low = i2c_readAck(); //Read 1 byte and then send ack
data_high = i2c_readAck(); //Read 1 byte and then send ack
pec = i2c_readNak();
i2c_stop();
//This converts high and low bytes together and processes temperature, MSB is a error bit and is ignored for temps
double tempFactor = 0.02; // 0.02 degrees per LSB
double tempData = 0x0000;
int frac;
// This masks off the error bit of the high byte, then moves it left 8 bits and adds the low byte.
tempData = (double)(((data_high & 0x007F) << 8) + data_low);
tempData = (tempData * tempFactor)-0.01;
tempData = tempData - 273.15;
Serial.print((int)tempData); //Print temp in degrees C to serial
Serial.print(".");
tempData=tempData-(int)tempData;
frac=tempData*100;
Serial.println(frac);
delay(100);
}
Is there any reason the code isnt working? i tried using Serial.println to see till what stage the program executes and it stops before
i2c_rep_start(dev+I2C_READ);
doesnt go beyond that
Any ideas?
Also does the 5v version require me to pull-up to 5v or 3.3because thts SMBus spec?
Also the melexis datasheet gives a figure which shows the pin configurations and is labelled "TOP VIEW"
Does that mean it shows the pins coming out of the page or the other way round??
Im confused