I had some spare time (Ya… like I always have at my age)
I was having a bit of a problem with I2C and I found some old code by GHI and it got me brain working again.
Posting for anybody that needs something to get them started.
Nothing pretty but it worked!
/*
Based on GHI Electronics Source Code
ghi_elect-gadgeteer-5c8596ffc9f6.zip
TempHumidSI70_43.cs (namespace Gadgeteer.Modules.GHIElectronics)
Using a USB FTDI 3.3V cable for serial. (PC using Tera Term)
Pin
1 Black Ground To 8 pin header GND(Arrow Mark on connector)
2 Brown CTS# (Not used)
3 Red VCC(+5V) (Not used)
4 Orange TXD To 8 pin header COM1 RX <--- 8 pin header D0 COM1
5 Yellow RXD To 8 pin header COM1 TX <--- 8 pin header D1 COM1
6 Green RTS# (Not used)
Using a Panda III
Using a TempHumid SI70 Gadgeteer Module and Breakout Module
Breakout pin Gnd to Panda III Gnd
Breakout pin 3V3 to Panda III 3V3
Breakout pin P4 to Panda III 8 Pin Header D3 (I2C_SCL)
Breakout pin P5 to Panda III 8 Pin Header D2 (I2C_SDA)
PB7/I2C1/SDA Cpu Pin 93 - X2 8 pin header Pin 3 - D2
PB6/I2C1/SCL Cpu Pin 92 - X2 8 pin header Pin 4 - D3
*/
using System;
using System.Threading;
using GHIElectronics.TinyCLR.Pins;
using GHIElectronics.TinyCLR.Devices.Gpio;
using GHIElectronics.TinyCLR.Devices.I2c;
using GHIElectronics.TinyCLR.Devices.Enumeration;
using GTC_DS = GHIElectronics.TinyCLR.Devices.SerialCommunication;
using GTC_SS = GHIElectronics.TinyCLR.Storage.Streams;
namespace TinyCLR_I2C_Test
{
public class Program
{
private static bool loop = true;
// On board LED
public static GpioPin LED4; //Red PE9/PWM0
// I2C1
private static I2cDevice I2c;
public static GpioPin SCL;
public static GpioPin SDA;
// Serial
private static GTC_DS.SerialDevice _com1;
private static GTC_SS.IOutputStream _outStream;
private static GTC_SS.IInputStream _inStream;
private static char[] charsToTrim = { '-', '0' };
private static GTC_SS.Buffer _Serialmsgbuffer;
private static GTC_SS.Buffer _Serialreadbuffer;
//
// * Slave address *
private static byte I2C_ADDRESS = 0x40; // Dec. 64 Bin. 01000000
// * Measure Relative Humidity, Clock stretching (Hold Master Mode) *
private static byte MEASURE_HUMIDITY_HOLD = 0xE5; // Dec. 229 Bin. 1110 0101
// * Read Temperature Value from Previous RH Measurement *
private static byte READ_TEMP_FROM_PREVIOUS = 0xE0; // Dec. 224 Bin. 1110 0000
// Measure Relative Humidity, No Hold Master Mode
//private static byte RH_NOHOLD = 0xF5; // Dec. 245 Bin. 1111 0101
// Measure Temperature, Clock stretching (Hold Master Mode)
//private static byte TEMP_HOLD = 0xE3; // Dec. 227 Bin. 1110 0011
// Measure Temperature, No Hold Master Mode
//private static byte TEMP_NOHOLD = 0xF3; // Dec. 243 Bin. 1111 0011
// Reset
//private static byte RESET = 0xFE; // Dec. 254 Bin. 1111 1110
// Write RH/T User Register 1
//private static byte WRITE_USER_REG = 0xE6; // Dec. 230 Bin. 1110 0110
// Read RH/T User Register 1
//private static byte READ_USER_REG = 0xE7; // Dec. 231 Bin. 1110 0111
// Write Heater Control Register 0x51 // Dec. 81 Bin. 0101 0001
// Read Heater Control Register 0x11 // Dec. 17 Bin. 0001 0001
private static byte[] I2CwriteBuffer1;
private static byte[] I2CwriteBuffer2;
private static byte[] I2CreadBuffer1;
private static byte[] I2CreadBuffer2;
private static bool blink = false;
public static void Main()
{
var gpio = GpioController.GetDefault();
// PC Board Red LED PE9/PWM0 CPU Pin 40
LED4 = gpio.OpenPin(FEZPandaIII.Gpio.Led4);
LED4.SetDriveMode(GpioPinDriveMode.Output);
// COM port using a USB FTDI 3.3V cable for serial. (PC using Tera Term)
_com1 = GTC_DS.SerialDevice.FromId("COM1");
_outStream = _com1.OutputStream;
_inStream = _com1.InputStream;
// Returns one I2C device and 4 SPI devices
// Devices Returns [0] = "I2C1", [1] = "SPI1", [2] = "SPI2", [3] = "SPI3", [4] = "SPI4"
var Devices = DeviceInformation.FindAll(FEZPandaIII.I2cBus.I2c1);
// Device I2C1 Slave address
I2cConnectionSettings Setting = new I2cConnectionSettings(I2C_ADDRESS);
//Setting.BusSpeed = I2cBusSpeed.StandardMode; // 100kHz
// Or
Setting.BusSpeed = I2cBusSpeed.FastMode; // 400kHz
I2c = I2cDevice.FromId(Devices[0].Id, Setting);
SendMsg("\r\n Type a upper case Q to exit the while loop\r\n");
SendMsg("\r\n Type a lower case t to read Temperature and RelativeHumidity\r\n");
SendMsg("\r\n i2c.DeviceId Dec: " + I2c.ConnectionSettings.SlaveAddress.ToString() +
" Hex: " + I2c.ConnectionSettings.SlaveAddress.ToString("X"));
SendMsg("\r\n i2c.BusSpeed " + I2c.ConnectionSettings.BusSpeed.ToString());
SendMsg("\r\n StandardMode = 0 - FastMode = 1\r\n");
// Here we go
while (loop)
{
ToggleLED();
_Serialreadbuffer = new GTC_SS.Buffer(2);
if (_inStream.Read(_Serialreadbuffer, _Serialreadbuffer.Capacity, GTC_SS.InputStreamOptions.None) > 0)
{
byte[] b = _Serialreadbuffer.Data;
string stng = b.GetValue(0).ToString();
// Q ascii - 81 Dec , 51 Hex
// q ascii - 113 Dec , 71 Hex
if (stng == "81") // Is character received a uppercase Q?
{
SendMsg("\r\n !!! Upper case Q received. Exit while loop.");
SendMsg("\r\nReset the board.\r\n");
loop = false;
}
//
if (stng == "114") //Char r - 114 Dec , 0X72 Hex
{
//Read (Not used)
SendMsg("\r\n The r key was pressed\r\n");
}
//
if (stng == "119") //Char w - 119 Dec , 0x77 Hex
{
//Write (Not used)
SendMsg("\r\n The w key was pressed (write)\r\n");
}
//
//
if (stng == "116") //Char t - 119 Dec , 0x74 Hex
{
SendMsg("\r\n The t key was pressed - I2C test\r\n");
TempHumidity();
}
//
}
//
Thread.Sleep(500);
}
// while
SendMsg("\r\nExit while()\r\n");
}
// Main
private static void TempHumidity()
{
I2CwriteBuffer1 = new byte[1] { MEASURE_HUMIDITY_HOLD }; //0xE5
I2CwriteBuffer2 = new byte[1] { READ_TEMP_FROM_PREVIOUS }; //0xE0
I2CreadBuffer1 = new byte[2];
I2CreadBuffer2 = new byte[2];
I2c.WriteRead(I2CwriteBuffer1, I2CreadBuffer1);
Thread.Sleep(10);
I2c.WriteRead(I2CwriteBuffer2, I2CreadBuffer2);
int rawRH = I2CreadBuffer1[0] << 8 | I2CreadBuffer1[1];
int rawTemp = I2CreadBuffer2[0] << 8 | I2CreadBuffer2[1];
SendMsg("\r\n rawRH " + rawRH.ToString());
SendMsg("\r\n rawTemp " + rawTemp.ToString() + "\r\n");
double temperature = 175.72 * rawTemp / 65536.0 - 46.85;
double relativeHumidity = 125.0 * rawRH / 65536.0 - 6.0;
if (relativeHumidity < 0.0)
{
relativeHumidity = 0.0;
}
if (relativeHumidity > 100.0)
{
relativeHumidity = 100.0;
}
SendMsg("\r\n Celsius: " + temperature.ToString("F1"));
SendMsg("\r\n Fahrenheit: " + (temperature * 1.8 + 32.0).ToString("F1"));
SendMsg("\r\n RH: " + relativeHumidity.ToString("F1") + "\r\n");
}
//
// PC Board Red LED
private static void ToggleLED()
{
if (blink)
{
LED4.Write(GpioPinValue.High);
}
else
{
LED4.Write(GpioPinValue.Low);
}
//
blink = !blink;
}
//
private static void SendMsg(string theMsg)
{
// Send theMsg to the serial terminal.
_Serialmsgbuffer = new GTC_SS.Buffer(System.Text.Encoding.UTF8.GetBytes(theMsg));
_outStream.Write(_Serialmsgbuffer);
}
//
private static byte[] GetBytes(string theMsg)
{
return System.Text.Encoding.UTF8.GetBytes(theMsg);
}
//
} // Class
} // Namespace
//
Thanks GHI for the code!
