delbiorobi

I'm having the same issues with my TC74 sensor. I'm new to the C# world. Could you post your entire VisualStudio solution? So I could learn from it? Thanks.

 

 

namespace TCN75A example{    public class Program    {        private static Byte[] rxbuffer = new Byte[2];         private static I2CDevice tempSensor;         private static int tempReg = 0;        private static float tempValue = 0;              public static void Main()        {            tempSensor = new I2CDevice(new I2CDevice.Configuration(0x48, 400));            I2CDevice.I2CTransaction[] settings = new I2CDevice.I2CTransaction[]            {                I2CDevice.CreateWriteTransaction(new Byte[] { 0x01, 0x60 }),            };            tempSensor.Execute(settings, 500);            TimerCallback tempDelegate = new TimerCallback(tempRead);            Timer tmrTemperature = new Timer(tempDelegate, null, 0, 60000);			public static void tempRead(Object currentTime)			{				I2CDevice.I2CTransaction[] rd = new I2CDevice.I2CTransaction[]						{							I2CDevice.CreateWriteTransaction(new Byte[] { 0x00 }),							I2CDevice.CreateReadTransaction(rxbuffer)						};				tempSensor.Execute(rd, 500);				tempReg = rxbuffer[0];				tempReg = tempReg << 8;				tempReg += rxbuffer[1];				tempReg = tempReg >> 4;				tempValue = (float)tempReg / 16;			}		}	}	}

I2CDevice.CreateWriteTransaction(new byte[] { 0x01, 0x60 })

try this.

Yes, it works!
Thank you very much NooM.

It seems that

I2CDevice.I2CTransaction[] settings = new I2CDevice.I2CTransaction[]
            {
                I2CDevice.CreateWriteTransaction(new Byte[1] { 0x01 }),
                I2CDevice.CreateWriteTransaction(new Byte[1] { 0x60 })
            };

is unable to write the registers of TCN75A.
0x01 point to config register, and 0x60 change the temperature resolution, but output value is not affected to these changes.
Someone else uses it and has the same problem?

using System;
using System.Threading;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using SecretLabs.NETMF.Hardware;
using SecretLabs.NETMF.Hardware.NetduinoPlus;

namespace NetduinoPlus_Temp_01
{
    public class Program
    {
        public static void Main()
        {
            Byte[] rx = new Byte[2];
            int tempreg = 0;
            float temperature = 0;

            I2CDevice.Configuration config = new I2CDevice.Configuration(0x48, 400);

            I2CDevice sensore = new I2CDevice(config);

            I2CDevice.I2CTransaction[] settings = new I2CDevice.I2CTransaction[]
            {
                I2CDevice.CreateWriteTransaction(new Byte[1] { 0x01 }),
                I2CDevice.CreateWriteTransaction(new Byte[1] { 0x60 })
            };

            I2CDevice.I2CTransaction[] rd = new I2CDevice.I2CTransaction[]
            {
                I2CDevice.CreateWriteTransaction(new Byte[1] { 0x00 }),
                I2CDevice.CreateReadTransaction(rx)
            };

            sensore.Execute(settings, 500);

            while (true)
            {
                sensore.Execute(rd, 500);

                tempreg = rx[0];
                tempreg = tempreg << 8;
                tempreg += rx[1];
                tempreg = tempreg >> 4;

                temperature = (float)tempreg / 16;

                Debug.Print("Temperatura attuale: " + temperature.ToString() + "°C");

                Thread.Sleep(2000);
            }

        }
    }
}

Thank you Noom,
the problem was pull-up resistors; i was convinced that they were integrated into the temperature sensor board, but it's not: now i can read temperature output.
I'm trying your class, very useful, because i'll use 3 or 4 sensor with I²C.

did you use pull-up resistors on your wiring?