I have a Temp/Humidity sensor breakout board from Sparkfun. The sensor literature says the 2 wires act like IC2 but there is no device addressing so I have been using 0 as the address. When I send it a command I do not get any bytes returned and of course I can get no data back. I have wired Vcc to either the 3.3V out or the 5V in/out, the ground to ground, Data line to Di2, and the Clock line to Di3. I have downloaded the latest GHI SDK and updated the firmare. The display board works fine, but the sensor seems to be dead in the water. Here is my C# class:
using System;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using GHIElectronics.NETMF.Hardware;
using System.Threading;
namespace USBizi_GraphicsSupport
{
public class SHT15I2C
{
#region constants
private const int clockRateKHz = 10;
private byte[] REGISTER_Control = new byte[] {0x01}; //command to configure sensor
private const byte REGISTER_Temperature = 0x00; //command to request result
private const byte CONTROL_EnergyModeShutdown = 0x01;
private const byte CONTROL_DataLengthTwelveBits = 0x60;
private const byte CONTROL_OneShot = 0x80;
//ms The maximum time needed by the sensor to convert 12 bits
private const int conversionTime = 600;
private const int transactionTimeout = 50; //ms
//adr command r/w
byte STATUS_REG_W = 0x06; //000 0011 0
byte STATUS_REG_R = 0x07; //000 0011 1
byte MEASURE_TEMP = 0x03; //000 0001 1
byte MEASURE_HUMI = 0x05; //000 0010 1
byte RESET = 0x1e; //000 1111 0
//Read Buffer
byte[] inBuffer = new byte[3];
#endregion
I2CDevice.Configuration config = new I2CDevice.Configuration(100, clockRateKHz);
private readonly byte address;
//Init I2C Device & Read/Write Transactions
I2CDevice tempSensor;
I2CDevice.I2CWriteTransaction writeTrans;
I2CDevice.I2CReadTransaction readTrans;
public SHT15I2C()
{
Cpu.Pin sck;
Cpu.Pin data;
HardwareProvider.HwProvider.GetI2CPins(out sck, out data);
Cpu.Pin msk;
Cpu.Pin miso;
Cpu.Pin mosi;
HardwareProvider.HwProvider.GetSpiPins(SPI.SPI_module.SPI1,out msk,out miso,out mosi);
tempSensor = new I2CDevice(config);
byte[] reset = new byte[1] { RESET };
writeTrans = tempSensor.CreateWriteTransaction(reset);
readTrans = tempSensor.CreateReadTransaction(inBuffer);
I2CDevice.I2CTransaction[] transactions = new I2CDevice.I2CTransaction[] { writeTrans, readTrans };
int bytesSent = tempSensor.Execute(transactions, transactionTimeout);
}
public void Dispose()
{
tempSensor.Dispose();
config = null;
writeTrans = null;
readTrans = null;
}
public void GetTemperature()
{
//byte[] temperatureCommand = { 0, 0, 0, 0, 0, 0,1,1 }; // command used to read temperature
byte[] tempCommand = new byte[1] { MEASURE_TEMP };
I2CDevice.I2CTransaction writeTempCommandTrans = tempSensor.CreateWriteTransaction(tempCommand);
I2CDevice.I2CTransaction[] tempTransactions = new I2CDevice.I2CTransaction[] { writeTempCommandTrans, readTrans };
int bytesSent = tempSensor.Execute(tempTransactions, transactionTimeout);
//the conversion time is the maximum time
//it takes the sensor to convert a physical reading to bits
Thread.Sleep(transactionTimeout);
byte[] regCommand = new byte[1] { STATUS_REG_W };
I2CDevice.I2CTransaction writeResultsTrans = tempSensor.CreateWriteTransaction(regCommand);
I2CDevice.I2CTransaction[] resultsTransactions = new I2CDevice.I2CTransaction[] { writeResultsTrans, readTrans };
bytesSent = tempSensor.Execute(resultsTransactions, transactionTimeout);
byte result1 = inBuffer[0];
byte result2 = inBuffer[1];
return;
}
}
}
Any suggestions?
