public void InitTest()
{
List<byte> packet = new List<byte> ();
var sht21 = new SHT21 ();
sht21.Reset ();
// Check the serial number in on-chip memory 1
// TODO: not fully implemented, now returns zeros
packet.Add ((byte)0xFC);
packet.Add ((byte)0xFA);
packet.Add ((byte)0x0F);
sht21.Write (packet.ToArray ());
packet.Clear ();
byte[] serialNr = sht21.Read ();
Assert.AreEqual (serialNr[0], 0x0);
Assert.AreEqual (serialNr[1], 0x0);
Assert.AreEqual (serialNr[2], 0x0);
Assert.AreEqual (serialNr[3], 0x0);
Assert.AreEqual (serialNr[4], 0x0);
Assert.AreEqual (serialNr[5], 0x0);
Assert.AreEqual (serialNr[6], 0x0);
Assert.AreEqual (serialNr[7], 0x0);
Assert.AreEqual (serialNr[8], 0x0);
// Check the serial number in on-chip memory 2
// TODO: not fully implemented, now returns zeros
packet.Add ((byte)0xFD);
packet.Add ((byte)0xFA);
packet.Add ((byte)0xC9);
sht21.Write (packet.ToArray ());
packet.Clear ();
serialNr = sht21.Read ();
Assert.AreEqual (serialNr[0], 0x0);
Assert.AreEqual (serialNr[1], 0x0);
Assert.AreEqual (serialNr[2], 0x0);
Assert.AreEqual (serialNr[3], 0x0);
Assert.AreEqual (serialNr[4], 0x0);
Assert.AreEqual (serialNr[5], 0x0);
Assert.AreEqual (serialNr[6], 0x0);
// Check the user register, write and read back
byte userWrite = 0xAA;
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE6);
packet.Add (userWrite);
sht21.Write (packet.ToArray ());
packet.Clear ();
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE7);
sht21.Write (packet.ToArray ());
packet.Clear ();
byte[] userRead = sht21.Read ();
Assert.AreEqual (userRead[0], userWrite);
// Do a soft reset and check reset value of user register
packet.Add ((byte)0xFD);
packet.Add ((byte)0xFE);
packet.Add ((byte) 0x0);
sht21.Write (packet.ToArray ());
packet.Clear ();
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE7);
sht21.Write (packet.ToArray ());
packet.Clear ();
userRead = sht21.Read ();
Assert.AreEqual (userRead[0], 0x3A);
}
public void ReadTemperatureTest()
{
List<byte> packet = new List<byte> ();
var sht21 = new SHT21 ();
sht21.Reset ();
// Start measurement, Temperature - hold master
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE3);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Read temperature sensor data result
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE3);
sht21.Write (packet.ToArray ());
packet.Clear ();
byte[] temperatureBytes = sht21.Read ();
// Check SHT21 CRC
// Check SHT21 CRC
byte[] resultArray = new byte[2] { 0, 0};
resultArray[0] = temperatureBytes[0];
resultArray[1] = temperatureBytes[1];
byte checkCRC = GetSTH21CRC(resultArray, 2);
Assert.AreEqual(checkCRC, temperatureBytes[2]);
// Assemble data bytes - default precision value is 14 bit
UInt16 temperatureInt = (UInt16)((((int)temperatureBytes[0] << 6) & 0x3FC0) + (((int)temperatureBytes[1] & 0xFC)>>2));
// Calculate temperature
// T = -46.85 + 175.72 * ST/2^16
double temperature = 17572.0*Convert.ToDouble(temperatureInt)/65536.0 - 46.85;
temperature = Math.Round(temperature, 2);
Assert.Greater (temperature, 0);
}
public void ReadHumidityTest()
{
List<byte> packet = new List<byte> ();
var sht21 = new SHT21 ();
sht21.Reset ();
////////////////////////////////////////////////////////////
// Start measurement, Relative Humidity - hold master - 12-bit resolution
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Read Relative Humidity sensor data result
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
byte[] humidityBytes = sht21.Read ();
// Check SHT21 CRC
byte[] resultArray = new byte[2] { 0, 0};
resultArray[0] = humidityBytes[0];
resultArray[1] = humidityBytes[1];
byte checkCRC = GetSTH21CRC(resultArray, 2);
Assert.AreEqual(checkCRC, humidityBytes[2]);
// Assemble data bytes - default precision value is 12 bit
UInt32 humidityInt = (UInt32)((((UInt16)humidityBytes[0] << 4) & 0xFF0) + (((UInt16)humidityBytes[1]>>4) & 0xF));
// Calculate relative humidity
// RH = -6 + 125 * SRH/2^16
double humidity = 125.0*Convert.ToDouble(humidityInt << 4)/65536.0 - 6.0;
humidity = Math.Round(humidity, 1);
Assert.Greater (humidity, 0);
Assert.LessOrEqual (humidity, 100);
////////////////////////////////////////////////////////////
// Start measurement, Relative Humidity - hold master - 8-bit resolution
// Set 8-bit resolution
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE6);
packet.Add ((byte)0x3B);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Start measurement
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Read Relative Humidity sensor data result
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
humidityBytes = sht21.Read ();
// Check SHT21 CRC
resultArray = new byte[2] { 0, 0};
resultArray[0] = humidityBytes[0];
resultArray[1] = humidityBytes[1];
checkCRC = GetSTH21CRC(resultArray, 2);
Assert.AreEqual(checkCRC, humidityBytes[2]);
// Assemble data bytes - precision value is 8 bit
humidityInt = (UInt32)(humidityBytes[0] & 0xFF);
// Calculate relative humidity
// RH = -6 + 125 * SRH/2^16
humidity = 125.0*Convert.ToDouble(humidityInt << 8)/65536.0 - 6.0;
//humidity *= 100;
humidity = Math.Round(humidity, 1);
Assert.Greater (humidity, 0);
Assert.LessOrEqual (humidity, 100);
// Start measurement, Relative Humidity - hold master - 8-bit resolution
// Set 10-bit resolution
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE6);
packet.Add ((byte)0xBA);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Start measurement
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Read Relative Humidity sensor data result
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
humidityBytes = sht21.Read ();
// Check SHT21 CRC
resultArray = new byte[2] { 0, 0};
resultArray[0] = humidityBytes[0];
resultArray[1] = humidityBytes[1];
checkCRC = GetSTH21CRC(resultArray, 2);
Assert.AreEqual(checkCRC, humidityBytes[2]);
// Assemble data bytes - precision value is 10 bit
humidityInt = (UInt32)((((UInt16)humidityBytes[0] << 2) & 0x3FC) + (((UInt16)humidityBytes[1]>>6) & 0x3));
// RH = -6 + 125 * SRH/2^16
humidity = 125.0*Convert.ToDouble(humidityInt << 6)/65536.0 - 6.0;
//humidity *= 100;
humidity = Math.Round(humidity, 1);
Assert.Greater (humidity, 0);
Assert.LessOrEqual (humidity, 100);
// Start measurement, Relative Humidity - hold master - 8-bit resolution
// Set 11-bit resolution
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE6);
packet.Add ((byte)0xBB);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Start measurement
packet.Add ((byte)0xFD);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
// Read Relative Humidity sensor data result
packet.Add ((byte)0xFC);
packet.Add ((byte)0xE5);
sht21.Write (packet.ToArray ());
packet.Clear ();
humidityBytes = sht21.Read ();
// Check SHT21 CRC
resultArray = new byte[2] { 0, 0};
resultArray[0] = humidityBytes[0];
resultArray[1] = humidityBytes[1];
checkCRC = GetSTH21CRC(resultArray, 2);
Assert.AreEqual(checkCRC, humidityBytes[2]);
// Assemble data bytes - precision value is 11 bit
humidityInt = (UInt32)((((UInt16)humidityBytes[0] << 3) & 0x7F8) + (((UInt16)humidityBytes[1]>>5) & 0x7));
// Calculate relative humidity
// RH = -6 + 125 * SRH/2^16
humidity = 125.0*Convert.ToDouble(humidityInt << 5)/65536.0 - 6.0;
//humidity *= 100;
humidity = Math.Round(humidity, 1);
Assert.Greater (humidity, 0);
Assert.LessOrEqual (humidity, 100);
}
