Sweet! My younger brother is wanting to do exactly what you are doing. I'll let him know! Scott...

Michael, Dan:

You are precisely correct. The RTM was scheduled to ship on Monday of this week so we decided it wouldn't make sense to have an RC2 for a week only to replace it by the RTM version. Also, the new AnalogPort/AnalogInput class was still being changed post-RC2 and we wanted that to settle before we integrated in the SAM7X-specific code.

We're going to build an "RC3" firmware to match the .NET MF 4.2 firmware...to make sure that users don't experience any BSOD issues. This should be the first "release-quality" 4.2 firmware. From there, we'll take input from users and get things ready for an official 4.2 firmware release (and pull in the new PWM and AnalogInput objects). We may do a few RCs until the community tells us that we're good to go--but that process should go pretty quickly.

I'm excited about 4.2. In addition to VB support and GC bugfixes, there are also new features and networking enhancements. Thanks to the testing and feedback of the NETMF community, this will likely be the highest quality NETMF release to date.

Chris

Have they fixed the "unplug the USB / replug the USB" everytime you want to deploy bug?

Scott...

Hi Mike,

Are you writing large amounts of info out via Debug.Print? This can happen if the debug output stream is too busy and Visual Studio "can't get a word in edge-wise..."

Otherwise, this might be a good issue to bring up on the netmf.codeplex.com site...a recommendation for something to tweak in the desktop-side SDK.

Chris

Any update on this bug? Looks like they recommended some firmware changes on Codeplex, but thats the last thing I saw that indicated any progress had been made on resolution.

Scott...

Hi Scott,

If you erase your current app (using the Erase button in MFDeploy), do you have the same deployment issue?

Unfortunately, it seems like this is an issue specific to certain computer hardware. If you can consistently reproduce it with the latest .NET MF 4.2 release, please post a bug report on netmf.codeplex.com.

Chris

Spent all of the long weekend coding / debugging. Probably spent more time unpluging the Netduino+ than I actually did debugging and coding.

Erasing the app seems to work about 50% of the time. Again, I'm running the 4.1.1 Onewire Alpha firmware. I'd love to try the 4.2 RC but I've not seen a onewire build for that version yet. Couple of questions:

1) Not sure what everyone means by blue screen of death. Are you talking about the PC BSODing when you unplug, or the Netduino? Not sure how the netduino BSODs, but I know what a PC BSOD is, and that is not happening to me. Basically what happens is that the deployment just freezes. I have to unplug / replug the netduino 2 or more time to get it to work. Question: Is the 4.2 update causing the PC to BSOD on usb unplug during deployment? If so, I definately dont want to add more frustration to the process to have to reboot every time I change 1 line of code during a debug session.

2) Is there still additional data that is needed from users to resolve this problem? I see quite a bit of back and forth on Codeplex, but I do not see any mention of having everything that is needed to solve the issue.

Scott...

Chris, Has there been any real progress on getting this bug fixed? This first report I see of this on Codeplex was way back in June and it doesn't look like any progress has been made towards resolution. Does the forum software have the ability to take a vote? Seems like it would be good to know how many people are affected by this bug. Scott...

Got the same problem here with the 4.2RC1, a power cycle of the interface is required before every deploy.

So this is the latest update on this problem from the Codeplex site...

Comments
lorenzte wrote Today at 5:33 PM
Several suggestions are in the hands of SecretLabs to produce a new firmware image.


sagreen83 wrote Today at 5:02 PM
Has any progress been made fixing this bug?


Has the new firmware image been created? If so, does it fix the problem?

Scott...

Bump...

I am running the 4.1.1 Onewire ALPHA firmware, and I have the same problem. Every time I want to move code over the the netduino I have to unplug USB power to get it to send the code over. I hit the reset button but it doesnt help. Interesting thing though. Seems like it should be completely unrelated, but this problem seems to happen more often the larger your code gets. When I first got my new netduino it was working fine with small programs, now I am up to the point where I only have about 20k free memory and I have the problem every time I try to debug or deploy. I'm hoping that the 4.2 release helps. Scott...

So I read all of the comments on CodePlex. Are they not able to recreate this problem? I can recreate it 100% of the time. I can never deploy my current app without having to unplug the USB cable and replug. It happens every time. This bug is so obvious I dont understand why they cant re-create it if that is the problem. Such a pain in the butt. Scott...

I bought a Sparkfun Serial LCD backpack http://seismo.sparkf...om/products/258 to hook up to one of my parallel 20x4 LCDs. Soldered it up, and the backpack/lcd works fine except I can only access 16x2 of the LCD. On the sparkfun site they show 16x2 and a 20x4 firmware for this backpack. I assume I need to flash the backpack with the 20x4 firmware. Problem is, I have no idea how to do this and Sparkfun is not showing up in their own forums to answer my question, so hoping some of you good people have an idea how I would do this. Questions: 1) Have any of you hooked this backpack up to a 20x4 LCD? 2) Do you have to reflash to use the 20x4 LCD? 3) How do I go about reflashing this? Do I need a pic programmer, or is there a way to flash it from a netduino? Thanks, Scott...

Awesome! Thank you, I'll give that a shot... Scott...

I want to read and store data from an accelerometer and I'm just wondering what the best practice is, or what the limitations are.
I have this accelerometer, and this is (hopefully soon) on it's way.

I'm just wondering what to do. I could:

• Try to write data to the SD-card as fast as possible directly from the x, y and z axis.
• Average the data using one or three threads and store the average value every second or so.
• Just pull a sample every second or so and store that.

I believe the first method would be best for analysis. I can run some tests and find the best algorithm for reating the data afterwards. However, can it be too much for the SD card, perhaps? Or how fast can the Netduino Plus sample data?

Method three is the easiest to implement, but I could be missing information I'm interessted in.

Method two is the one I'll use eventually, I believe, as it shouldn't be necessary to keep that much data.



If this had been a Windows application, I'd say just store the data and process them later. But on a little more limited hardware I'd like to know what I should do.

I am doing this exact same thing with my weatherstation project. http://forums.netdui...itor-webserver/

I use the netduino+ to sample the sensors. I have a single "stats" class that contains the values for each of the readings I am taking. So, the main program just calls a class to sample a sensor, gets that reading, and calls a stats class method to update the value for that sensor. In that method, I check to see if the value is higher or lower than my min/max values I have stored. If so, the class updates min and max, and saves a timestamp for min and max.

Every 1 second a thread wakes up and sends the values (via xml) over a socket to a server running on another PC. This server has the same stats class implemented, and it keeps averages every 1 minute, day, hour, week, month, year, and since inception. Every 1 minute a thread in the server wakes up and saves the 1 minute average to an XML log file that I can later pull into excel to do all of the trending that I want.

So, in a nutshell, isolate the main program from the statistical work via a stats class. Have the stats class summarize the data and write it where ever you want to. I chose to do this on a separate PC/Server because I was running low on memory on the netduino, and I want to write a web interface to the weatherstation. Too much work for the netduino+ IMHO.

Hope that helps,
Scott...

Using a Tektronics MSO 2012 (100 MHz) scope, I observed over 1 volt of noise on the 5 volt supply, all of it negative going. I am assuming the actual noise is greater than what I observed due to the limitations of my scope's bandwidth. Also the MAX chip should ignore the noise unless it is greater than that. I observed that the noise disappears if the reset button is held down, indicating to me that the CPU and/or the Ethernet/PHY chip is creating the noise by requiring different current draws as it runs.

I am assuming the 10uF caps on the Netduino Plus's linear supplies are not large enough to handle the short term spikes in current demand. What noise levels have you seen?

Robert,

I saw the same thing with both my 5V and 3.3V lines coming from my netduino+. I switched over to powering the netduino with a wall wart, and added dedicated 5V and 3.3V regulators to my circuit supplied from the VIN line on the netduino. Smoothed the supply voltage right out.

Scott...

FANTASTIC! The One-Wire code in the firmware appears solid to me. I haven't seen any issues with it. Although, I really wanted to see a much simpler and object oriented way of working with 1 wire, so I wrote a wrapper class (called OneWireNetwork) out of CW2's sample. I only tested it with my DS18B20 sensors, but I have more coming soon and hopefully will add classes for them. So, what I did was create a collection class of devices that has a "Discover" method to scan the One-Wire network for devices. I hope this can be the start of a One-Wire framework that will make this the easiest One-Wire platform available. I have attached the code to this post. It is a complete replacement for CW2's OneWireTestApp project from the first post. Also, this example works with 1, 2, 3, or more devices, using parasite power or not.

By using the library, the code gets very simple:

public static void Main()
    {
      // TODO: Change pin according to the actual wiring
      var deviceNetwork = new OneWireNetwork(Pins.GPIO_PIN_D0);
          
      // Interrogate the devices on the network (adding them to the collection)
      deviceNetwork.Discover();

      while (true)
      {
          // Loop through all the discovered devices
          foreach (var aDevice in deviceNetwork)
          {
              Debug.Print("Address: " + aDevice.Address);
              
              if (aDevice is DS18B20) 
                  Debug.Print("Temp: " + (aDevice as DS18B20).Temperature);
          }

          Thread.Sleep(20000);
      }
    }

Output:

1-Wire device present
Multiple devices present
72000002DC320128
B2000002DC405128
54000002DC577D28
Address: 000002DC3201
Temp: 23.375
Address: 000002DC4051
Temp: 23.4375
Address: 000002DC577D
Temp: 23.5
The program '[16] Micro Framework application: Managed' has exited with code 0 (0x0).

Things still to add:
Support for reading and writing to the device memory
Throw Events for device alerts
Robust exception handling
Throw Events for devices being added or removed
Support for a variety of One-Wire devices
Automatic instantiation of classes based on detected device family (should probably use some Reflection here)

I think CW2's firmware should get included into the next Beta. Let's get more people trying to use it...

*** Thanks again to CW2 ***

-Valkyrie-MT

Valkyrie,

I noticed that ever time you call Discover() it causes "foreach (var aDevice in gdeviceNetwork)" to add a new device to gDeviceNetwork...

May be intended, but if you put the discover in a loop, it adds a new device for every 1wire device you have on the network each time you call it. Seems like you should put a CRC check to make sure that the same device is not being added for each call...

FYI: I moved the Discover() call outside the loop, once at the top of Main() and it solved my problem..

Scott...

Sorry for the newb question, but can you tell me where I unzip the files for the example program prior to build and deploy? Firmware installed, just need to know where to put the unziped contents, and the DLL when built. Thanks, Scott...

IMHO the problem is that your oneWire object uses pin D0 that also has alternative function of being RxD of COM1 and it tries to reserve it during its initialization, which results in exception. To resolve the issue, you can use different pin for OneWire, e.g. D2, or switch to COM2 (D2, D3) for serial communication.

CW2, That did it! Thanks!

Scott...

Not entirely sure I understand your question, so I'll try to answer with some observations/facts.

• You must have this native driver to directly communicate with 1-wire devices (parasitic or not) with the Netduino (alternatively, you can use components like those from Peter Anderson)
• With this firmware, I can read from a mix of DS18B20, DS18S20, DS18B20PAR sensors some connected in parasitic mode (only 2 wires - ground and 1-wire signal) and others connected with the 5VDC (non-parasitic). I currently have 5 sensors connected - 3 are not parasitic and 2 are parasitic. That works fine.
• On occassion, I will get a bad read (think 1 in 50 reads) for whatever reason (possibly because I don't have a MOSFET as recommended), but with the CRC check, you always know, so I handle them easily. And usually, it won't happen twice on the same sensor.

-Valkyrie-MT

Valkyrie,

Can you elaborate on the CRC fix you are using to deal with the bad reads? I am getting some bogus temp readings as well..

Scott...

I'm trying to use the serial port to control a SparkFun serial LCD, and use the OneWire support of this firmware at the same time. I started out using both the DLL included with this release as well as the SerLCD class elsewhere in the forums. When I build either one by themselves, I can either write to the LCD or read 1wire temp sensors, but not both at the same time. I always get an InvalidOperation exception on the serial port open. So, to simplify the equation, I've added the following code to the OneWireTestApp. This just opens the serial port, writes a few lines to it, then starts waiting for button presses to read the temp sensor. I'm getting the same exception on the line lcd.Open(); Anyone else having this problem? public static byte[] getBytes(String message) { System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding(); return encoding.GetBytes(message); } public static void Main() { sw1 = new InterruptPort(Pins.ONBOARD_SW1, true, ResistorModes.Disabled, InterruptModes.InterruptEdgeLow); sw1.OnInterrupt += new NativeEventHandler(sw1_OnInterrupt); // TODO: Change pin according to the actual wiring oneWire = new OneWire(Pins.GPIO_PIN_D0); SerialPort lcd; lcd = new SerialPort(SerialPorts.COM1, 9600, Parity.None, 8, StopBits.One); lcd.ReadTimeout = 10; lcd.Open(); byte[] byteme = getBytes("Welcome to Netduino"); lcd.Write(byteme, 0, byteme.Length); byte[] bytes = new byte[1] { 12 }; lcd.Write(bytes, 0, bytes.Length); Thread.Sleep(Timeout.Infinite); }

Valkyrie,

wondering if you have gotten the CRC code (after an all channel voltage read) working with a DS2450. I know that its a 16 bit CRC, and the datasheet says that its calculated from Command Byte, Address Bytes, and Data Bytes. But I cant get a calculated 16bit CRC that matches the one that is sent back from the 2450. Heres, some test code...

var response = new byte[8];
var res2 = new byte[2];

var commandaddrdata = new byte[11]; // Array used to calculate the CRC16
var status = _core.Read(response); // Data Bytes
var stat2 = _core.Read(res2); // CRC bytes

commandaddrdata[0] = 0xAA;
commandaddrdata[1] = 0;
commandaddrdata[2] = 0;
commandaddrdata[3] = response[0];
commandaddrdata[4] = response[1];
commandaddrdata[5] = response[2];
commandaddrdata[6] = response[3];
commandaddrdata[7] = response[4];
commandaddrdata[8] = response[5];
commandaddrdata[9] = response[6];
commandaddrdata[10] = response[7];

var crc = OneWire.ComputeCRC16(response, count: 8);
var crcwithcommand = OneWire.ComputeCRC16(commandaddrdata, count: 11);

_LowByte = res2[1];
_HighByte = res2[0];
float DSCRC16 = (((UInt16)_HighByte << 8) | _LowByte);

Using this code DSCRC16 never matches crc or crcwithcommand. Have tried it with both inverted and non inverted high and low bytes on the read CRC.

Any ideas?

Thanks,
Scott...

For instance with temperature sensors, I've found that there are 2 kinds of bogus values. Ones corrupted in transmission (will fail CRC) and incomplete calculations from the sensors (which returns a default value that passes CRC). So, what I do is maintain the last sensor value in a variable and give that when requested. While at the same time, I routinely try to update the value. Below is the actual code I use for the sensor read with CRC and uninitialized value checking...

                // Write command and identifier at once
                var matchRom = new byte[9];
                Array.Copy(_rom, 0, matchRom, 1, 8);
                matchRom[0] = OneWire.MatchRom;

                _core.Reset();
                _core.Write(matchRom);
                _core.WriteByte(DS18X20.ReadScratchpad);
                System.Threading.Thread.Sleep(5);  // Wait Tconv (for default 12-bit resolution)

                var response = new byte[9];

                var status = _core.Read(response);
                var CRCPass = OneWire.ComputeCRC(response, count: 8) == response[8];
                var Initialized = OneWireExtensions.BytesToHexString(response.Range(0, 1)) != "0550";

                if (status == 9 && CRCPass && Initialized)
                {
                    if (this.FamilyCode == 0x28)
                    {
                        _lastTemp = ((short)((response[1] << 8) | response[0])) / 16F;
                    }
                    else if (this.FamilyCode == 0x10)
                    {
                        _lastTemp = (float)(((short)((response[1] << 8) | response[0])) >> 1) - 0.25F + ((float)(response[7] - response[6]) / (float)response[7]);
                    }
                    
                    _lastTempTime = DateTime.Now;

                    Debug.Print("Getting DS18X20 Temp - " + this.Address + ", " + _lastTemp.ToString());
                }

Also, the .Range method is just an extension method that returns an arrange of the requested range.

-Valkyrie-MT

Ok, after a ton of research, and a ton of code tests I figured it out... The DS2450 returns the CRC with the bytes swapped, and it inverts the bits within each byte. i.e. 0xFF = 0x00. The following code results in a good CRC calculation... A little code cleanup and I'm golden! var response = new byte[10]; var status = _core.Read(response); var commandaddrdata = new byte[11]; // Array used to calculate the CRC16 commandaddrdata[0] = 0xAA; commandaddrdata[1] = 0; commandaddrdata[2] = 0; commandaddrdata[3] = response[0]; commandaddrdata[4] = response[1]; commandaddrdata[5] = response[2]; commandaddrdata[6] = response[3]; commandaddrdata[7] = response[4]; commandaddrdata[8] = response[5]; commandaddrdata[9] = response[6]; commandaddrdata[10] = response[7]; UInt32 _LowInt = (UInt32) ~response[8] & 0xFF; // CRC Bits are inverted. Take complement of bits. UInt32 _HighInt = (UInt32) ~response[9] & 0xFF; UInt32 DSCRC16 = (((UInt32)_HighInt << 8) | _LowInt); var crcwithcommand = OneWire.ComputeCRC16(commandaddrdata, count: 11); if (crcwithcommand == DSCRC16) { channelA = (((Int16)response[1] << 8) | response[0]) * ConversionFactor; channelB = (((Int16)response[3] << 8) | response[2]) * ConversionFactor; channelC = (((Int16)response[5] << 8) | response[4]) * ConversionFactor; channelD = (((Int16)response[7] << 8) | response[6]) * ConversionFactor; } else { if (errorProc != null) errorProc(0, "DS2450 CRC Error. Return:" + DSCRC16.ToString() + " Calc:" + crcwithcommand.ToString()); }

I've been working on a standalone NetDuino+ solution that utilizes the following hardware.... Wind Speed / Wind Direction / Rain Fall - http://www.sparkfun.com/products/8942 Barometric Pressure - http://www.sparkfun.com/products/9694 OneWire temp sensor - http://www.sparkfun.com/products/245 Light Meter - Jameco part Serial LCD - http://www.sparkfun.com/products/9068 Door Switches - Jameco part Humidity - http://www.sparkfun.com/products/9569 I originaly built this so that I could check wind speed, and direction for flying RC Airplanes, but now I've decided to add some other things like monitoring Door Openings on my workshop, a WebServer so you can see instant weather stats and trends, etc. Is anyone remotely interested in this? If so, I'll start posting build log notes, pictures and code. I'm using a lot of stuff that others on the forums have contributed. Post a reply to this thread if you are interested in progress / code. Scott...

Hi Scott,

Where did you get the board mount wire holders (what I assume to be the function of the green and orange wire blocks in the last picture)? I have been looking for something that will hold some wires that are moved often a bit tighter than just plugging them into the breadboard directly.

Bought them from Sparkfun. http://www.sparkfun.com/products/10655 They also have screw terminals, but these work pretty good...

Scott...

Wow, ok... Here are a few pictures of the build... Scott...

Scanman, Super sorry about the reply delay. I totally missed your question. The weather station is pretty much done from a hardware perspective. I've attached 2 pictures, 1 of the disassembled final product, and one of the assembled weather monitor. What you are seeing is the monitoring hardware / home station. This consists of a circuit board that acts like a shield on the netduino. External to this box are an internal temp probe, an external box (outside) with Humidity, temp, Barometric pressure, and light level. There is also a weather station connection that provides wind speed, wind direction and rainfall. This monitor broadcasts packets to a dedicated windows server that tracks all of the weather statistics and provides a web based interface to the weather station. On the box is an LCD, LED and a Momentary switch. The LED blinks once for every revolution of wind, so I can visually see the wind speed from across the room. We routinely get 75mph winds where I live. The momentary pushbutton cycles through various LCD screens that give me instant access to all of the immediate weather stats. This was certainly a fun project. Probably pretty aggressive to take on as the 1st project with the netduino, but I had a great time doing it. Figured out how to create circuit boards on my CNC router which is a huge win for me! This will open up a whole new world of projects in the future. The DS1820 temp probes work well. I have no complaints about them at this point. You have to do some calibration between them, cause you will find that each one has slightly different temp readings, plus you have to make sure that you compensate for bad CRC values, and some bogus temp readings that you get from time to time. All in all, they are pretty easy to use with the 4.1.1 Alpha firmware. The one device that I am not happy with is the humidity sensor (Sparkfun). I've not found a super accurate way to read these things. The calculation requires a Zero humidity voltage reference value, and the only way you can get that is if you order it with the chip specific data sheet, and sparkfun does not supply that. Also, I get bogus reading from it all of the time. I think I can improve the logic to isolate the bogus readings, by ignoring huge second over second swings, but havent found a way to fix the reference problem. I'll keep hacking. Scott...

Making decent progress on the WeatherStation. Originally I was wanting to do all of the code on the Netduino, but got to the point where I was running out of memory. So, now I use the netduino to gather the sensor data and push it via a socket connection to a socket server app running on another PC. This push happens once per second. The server creates an XML file that contains one minute averages for all of the sensor data. I can pull this XML file into excel to see trends for all of the data points. I am logging: Wind Speed, Wind Direction, Rainfall, Inside Temp, Outside Temp, Barometric Pressure, Humidity and Light Level. Should be enough to do some cool weather monitoring. Running into a problem on the Netduino side. After about 6-7 hours of monitoring sensors, the netduino locks up and quits sending data to the server. It locks up to the point that its not accepting any interrupts anymore as well. I know this because I have an LED that fires every 1/2 revolution of the windspeed sensor, and it quits blinking. Not sure what is going on at this point, but I have narrowed it down to the point that I am reading from one of my onewire devices. Scott...