Sinan

I am trying to work with PWM but failed to access the onboard led. None of the examples found on the forum will function as expected.

 

The simple example below crashes on a Netduino1 with the 4.2.01 framework.

 

[font="'courier new', courier, monospace;"]using System;
using System.Threading;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using SecretLabs.NETMF.Hardware;
using SecretLabs.NETMF.Hardware.Netduino;

namespace NetduinoApplication1
{
  public class Program
  {
  public static void Main()
  {
  PWM pwm = new PWM(PWMChannels.PWM_ONBOARD_LED, 100, 0.5, false);
  pwm.Start();
  Thread.Sleep(Timeout.Infinite);
  }
  }
}[/font]

 

 

As soon as it hits the pwm initialization, the board freezes. After many variations of this code and too many erase&reboot sessions, I have checked the enumeration of the available PWMChannels.

 

[font="'courier new', courier, monospace;"]   Debug.Print("None: " + PWMChannels.PWM_NONE.ToString());
  Debug.Print("LED: " + PWMChannels.PWM_ONBOARD_LED.ToString());
  Debug.Print("Pin 3: " + PWMChannels.PWM_PIN_D3.ToString());
  Debug.Print("Pin 5: " + PWMChannels.PWM_PIN_D5.ToString());
  Debug.Print("Pin 6: " + PWMChannels.PWM_PIN_D6.ToString());
  Debug.Print("Pin 9: " + PWMChannels.PWM_PIN_D9.ToString());
  Debug.Print("Pin 10: " + PWMChannels.PWM_PIN_D10.ToString());
  Debug.Print("Pin 11: " + PWMChannels.PWM_PIN_D11.ToString());[/font]

 

Rather disturbing debug.print results:

[font="'courier new', courier, monospace;"]None: -1
LED: -1
Pin 3: -1
Pin 5: 0
Pin 6: 1
Pin 9: 2
Pin 10: 3
Pin 11: -1[/font]
 

 

Same code for PWM_Pin_D6 works as expected (checked with a logic analyzer).

 

Is the code freezing due to the missing mappings for these pins? And, can I do something to access the onboard led and the pins 3 and 11?

 

Regards, Sinan

Hi everyone,

I am trying to build a variometer using the Mod-1009 board for MS5611-01BA barometric pressure sensor from Embedded Adventures.

Unfortunately, I cannot read values from the i2c port. SDA is connected to Analog 4, SCLK to 5 and the VCC to 3.3v. I am using the latest framework (4.2).

I am OK with C# and .net but I am clueless in this world. Bellow is my code where the device.Execute always returns zero in the ReadFromDevice method.

using System;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;

namespace MS5611baro
{
  // Mod-1009 board for MS5611-01BA Barometric Pressure Sensor from
  // Embedded Adventures (http://www.embeddedadventures.com/barometric_pressure_sensor_module_mod-1009.html) 
  // MS5611 datasheet http://www.embeddedadventures.com/datasheets/ms5611.pdf
  // Mod-1009 description http://www.embeddedadventures.com/datasheets/MOD-1009_hw_v1.pdf
  // 
  // VCC  --> 3.3v
  // SDA  --> Analog 4
  // SCLK --> Analog 5
  // 
  // Pull up resistors: (from Mod-1009 description) The board comes with the pull-up resistors enabled. If you are
  //   connecting to an existing I2C buss that already has pull-up resistors, or you are using internal pull-ups in 
  //   your microcontroller, you can disable the pull-up resistors by cutting the PCB jumpers on the MOD-1009 board. 
  public class MS5611_MOD1009
  {
    private const byte _cmdReset = 0x1E;
    private const byte _cmdPromReadBase = 0xa0;
   
    private const ushort _i2cAddr = 0x76; //Embedded Adventures module CSB is VCC --> HIGH --> 0x76

    public UInt16[] CalibrationArray = new UInt16[6];
    public int LastTransactionCount = -1;

    private I2CDevice _device = new I2CDevice(new I2CDevice.Configuration(_i2cAddr, 10));

    /// <summary> Mod-1009 board for MS5611-01BA Barometric Pressure Sensor from Embedded Adventures</summary>
    public MS5611_MOD1009()
    {
      while (LastTransactionCount < 1)
      {
        WriteToDevice(_cmdReset, 100); // ResetSensor();       
      }
    }

    public bool WriteToDevice(byte command, int timeOut = 5)
    {
      I2CDevice.I2CWriteTransaction wt = I2CDevice.CreateWriteTransaction(new byte[] { command });
      LastTransactionCount = this._device.Execute(new I2CDevice.I2CTransaction[] { wt }, 3);
      return LastTransactionCount > 0;
    }

    public bool ReadFromDevice(byte[] readBuf, int timeOut = 100)
    {
      var rtArr = new I2CDevice.I2CReadTransaction[] { I2CDevice.CreateReadTransaction(readBuf) };
      LastTransactionCount = _device.Execute(rtArr, timeOut);  // --> returns allways zero
      return LastTransactionCount == readBuf.Length;
    }

    public void ReadCalibrationData()
    {
      for (byte i = 0; i < 6; i++)
      {
        CalibrationArray[i] = ReadSingleCalibrationValue((byte)(i + 1));
      }
    }

    private UInt16 ReadSingleCalibrationValue(byte valueToRead)
    {
      //  1 0 1 0 X X X 0  - The XXX part is used for the parameter index
      byte paramIndex = (byte)(_cmdPromReadBase + (valueToRead << 1));
      // This sets up the system into PROM read mode.
      if (WriteToDevice(paramIndex))       // --> returns true
      {
        byte[] readBuf = new byte[2];
        // This part gets the data from the system.
        if (ReadFromDevice(readBuf, 100)) // --> returns allways false, readBuf is empty {0, 0}
        {
          return (UInt16)(readBuf[0] << 8 | readBuf[1]);
        }
      }
      return 0;
    }
  }
}

using System;
using System.Threading;
using Microsoft.SPOT;

namespace MS5611baro
{
  public class Program
  {
    public static void Main()
    {
      var baro = new MS5611_MOD1009();
      baro.ReadCalibrationData();
    }
  }
}

Thanks for help,
Sinan