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#46335 Xbee to LCD using Netduino

Posted by AxelG on 27 February 2013 - 01:30 PM in Netduino 2 (and Netduino 1)

These XBee drivers are great.

 

Grommet

 

As well as this one:

 

GBee




#47341 Watchdog: How to do on netduino?

Posted by AxelG on 18 March 2013 - 06:49 PM in General Discussion

I have an extra board;happy to send it along... Just PM me.




#46645 Watchdog: How to do on netduino?

Posted by AxelG on 05 March 2013 - 01:08 AM in General Discussion

I have designs and plans to build a hardware watchdog you can use on a breadboard.  It is based on the MAX6373 chip.

 

I have posted the designs in another thread, or I can build one for you if you are interested.




#42927 small door sensor

Posted by AxelG on 07 January 2013 - 06:59 PM in Netduino 2 (and Netduino 1)

Another idea might be to wire a small piezo buzzer to the ND to also get an audio cue.

 

I have a home-built alarm system that will alert me to the opening or closing of a door or window while in standby.  Simple two beeps for open, one for closed.




#33957 Several stupid questions

Posted by AxelG on 20 August 2012 - 05:03 PM in Netduino 2 (and Netduino 1)

zajda:

Welcome. You can find a good review of bread boarding here:Bread Board They will also cover your question about LEDs. The wires used for bread boards will work nicely to connect to your Netduino.

Good luck and have fun.



#46682 Running ND+ and ND+2 on the same VM

Posted by AxelG on 05 March 2013 - 02:30 PM in Netduino Plus 2 (and Netduino Plus 1)

All of my ND and ND+ gen 1 and gen 2 are flashed to the latest firmware and everything running under 4.2 NETMF.

 

ND gen 1: 4.2.0.1

ND+ gen 1 4.2.0.1

ND+ gen 2 4.2.2.2

 

All the gen 1s are running WINUSB and gen 2 MFUSB on the latest  VM Player 5.0 Win7 ultimate 64 bit.

 

I can get all my gen 1 running OK together.  I have to reconnect them often in order to deploy and get into debug, but it is workable.

 

For the most part when running the gen 2 alone, deploying and debugging works OK.  If the gen 2 stops responding and needs to be disconnected; I will 100% of the time get a BSOD.  (It's not always fun having the ND+2 act as a hardware reset button in the middle of coding a project :) )




#46628 Running ND+ and ND+2 on the same VM

Posted by AxelG on 04 March 2013 - 08:29 PM in Netduino Plus 2 (and Netduino Plus 1)

Doe anyone have experience running a development environment with two Netduinos?  Specifically one ND+ and one ND+2?

 

I was getting BSOD and decided to rebuild my environment and now I can't seem to communicate with two NDs.  It will recognize one or the other but not both.

 

I can use ND and ND+ without a problem, it's only when I plus in the ND2...




#46492 NP2 reboots on deploy; never debugs/runs app

Posted by AxelG on 01 March 2013 - 03:02 PM in Netduino Plus 2 (and Netduino Plus 1)

Hi AxelG,The gen2 Netduinos use the MFUSB drivers, rather than the WinUSB drivers. There have been reports of issues with the WinUSB drivers and USB 3.0 ports...so while that bug is getting squashed we haven't switched the gen2 hardware to WinUSB. [For gen1 hardware, .NET MF 4.2 necessitated the move to WinUSB--because of the USB hardware architecture.]If Visual Studio has trouble deploying, press the Netduino's onboard board to reset the board. If that doesn't work, disconnect and reconnect and Visual Studio should find it (as you experienced previously). [And if you can find a simple repro where the pushbutton doesn't reset the board...please let us know, as there are things we can do to make the software-based reset even more resilient.] Chris

Thanks for the response Chris, and after re-installing I did notice the gen2 uses the older drivers.  I did notice less frequent hangs when I don't have gen1 and gen2 NDs plugged in at the same time.  However, when it does hang: hitting the reset button does the same as unplugging, my entire VM shuts down or get BSOD.




#46334 NP2 reboots on deploy; never debugs/runs app

Posted by AxelG on 27 February 2013 - 01:21 PM in Netduino Plus 2 (and Netduino Plus 1)

Same here.  I am running VMWare virtual machine Win7 with 4.2 NETMF and a ND2+ on 4.2.2.2. and VS 2010.   For some reason Windows wants to install and use MFUSB drivers not the WINUSB drivers.

 

When the ND locks up and I unplug it, my VM shuts down.  (nice feature!)

 

If I force WINUSB drivers, I can't see the ND on the USB bus and VS usually hangs up on deploy.

 

I have un-installed and re-installed both NETMF as well as Drivers without any effect.

 

My ND/MD+ will sometimes hang on deploy, but unplugging and plugging back in usually solves the problem.

 

Any additional ideas on troubleshooting would be great.




#46683 NP2 reboots on deploy; never debugs/runs app

Posted by AxelG on 05 March 2013 - 02:34 PM in Netduino Plus 2 (and Netduino Plus 1)

Thanks, I saw your reply in the other thread.  I decided to spin up a separate VM for gen2 development work.  I'll suck it up until WinUSB drivers are available for gen 2  :)   (No pressure....)

 

Honestly, thanks for all you do in support of this platform.  It's really appreciated.




#44747 Netduino Plus 2 Firmware v4.2.2 (update 1)

Posted by AxelG on 02 February 2013 - 04:03 AM in Netduino Plus 2 (and Netduino Plus 1)

Update went well, but now I am seeing a quirky problem reading from the SD card.  The following code hangs on the "while (reader.Peak())" line.  Stepping through the debugger looks like it is stuck in a loop...  Here is the code.  The file on the SD card has 10 lines of ascii data.

 

            ArrayList PortList = new ArrayList();            using (StreamReader reader = new StreamReader(PortFileName))            {                while (reader.Peek() > 0)                {                    HoldPort = new MCUPort(reader.ReadLine());                    HoldPort.State = 1;                    HoldPort.LastState = DateTime.Now;                    PortList.Add(HoldPort);                }            }



#44802 Netduino Plus 2 Firmware v4.2.2 (update 1)

Posted by AxelG on 03 February 2013 - 03:01 AM in Netduino Plus 2 (and Netduino Plus 1)

Thanks to Lunddahl and T!!

 

 

i also found that EndOfStream property is not set until AFTER the first access!!!  Before that it always reads "true".  If I use Peak() after opening the stream, and then change my while loop looking at EndOfStream it seems to work.

 

I will try looking at the solution T provided.  Thanks for your help!!




#43718 Netduino Plus 2 and LCD 20x4

Posted by AxelG on 19 January 2013 - 01:27 AM in Netduino Plus 2 (and Netduino Plus 1)

I used the same exact hardware on the ND and ND+ (version 1) and posed an article with light-weight driver here.




#33120 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 04 August 2012 - 07:08 PM in Beta Firmware and Drivers

I finally got around to upgrading to 4.2 to enable the SD card on my ND. Worked great. Took a bit of "translation" for the pinouts as it seems that nobody calls SPI pins the same thing. After getting that to function, I updated my code to 2.4 libraries, recompiled and now I am throwing the following error when opening up COM2: A first chance exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.dll A first chance exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll An unhandled exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll I change to COM1; everything is fine. I tried forcing Handshaking to be none (I am not using pins 7 or 8 for anything else, nor am I using pins 2 or 3 for anything else) Any ideas where I should look next? Runs fine on my ND+ under 4.1 (I am sure it is something obvious)



#33883 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 18 August 2012 - 11:24 PM in Beta Firmware and Drivers

Chris: I just confirmed that the same serial port issue exists in the latest 4.2 build (posted three days ago) If I use any flow control, I lose data. If I don't use flow control, I have to make sure to read data fast enough.... This happens with one ND, COM1 to COM2 or two netduinos connected with null-modem cable.



#33370 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 10 August 2012 - 01:02 PM in Beta Firmware and Drivers

Hi AxelG,

From the logic analyzer...can you tell where the data is being lost? Is it being lost on the Netduino (i.e. buffer overflow)?

Chris


If you look at the data in Data.jpg, that is the data coming from the XBee into the ND, and all of the bytes are in that stream. I can only assume the data is getting lost after it enters the Netduino. I am working on a Netduino to Netduino set of applications to reproduce. So far I am able to force the same exception I was seeing in the 4.1 release:

"A first chance exception of type 'System.ArgumentException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll
Exception: Exception was thrown: System.ArgumentException param name stack System.IO.Ports.SerialPort::Read
NDPlusSerialReader.Program+DoReader::Serial_DataReceived
System.IO.Ports.SerialPort::DataEventHandler"

I will post more later today.



#34567 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 02 September 2012 - 04:28 PM in Beta Firmware and Drivers

Any idea on what I should try next? I hit a wall with the serial port problems in this 4.2 build and really can't move forward until they are working.



#33348 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 10 August 2012 - 02:51 AM in Beta Firmware and Drivers

Unusual behavior with Serial Ports in 4.2 RC5 on ND and ND+ (Losing data…)

I have a project that requires two XBee/ZigBee modems to communicate and transfer large (for Zigbee) data packets from 1k to about 100k in size.

My plan is to use SD cards to buffer data as it come in and goes out the modems, stitching the packets together as they come in. Simple enough….

I am using the Grommet (Copyright © 2009 http://grommet.codeplex.com) drivers for the low-level networking, which I really like because they started out very light-weight and I made them lighter by removing some methods I will not need.

The project is too large to post the entire code base in this thread, but I plan to post later on as an extension of these drivers.

Here is my trouble: I am losing data after the receiving XBee passes it to the ND/ND+ and when it is read out of the serial buffer. Attached is the Logic trace showing data leaving XBee #1, and being passed from XBee #2 into the ND. The data loss happens at different places at different times. If I slow the transmissions way down (one message every two seconds) I get nearly zero lost bytes. As soon as I remove this delay; lost data.

Here is the setup:
  • ND with XBee1 and SD shield on SPI
  • ND+ with XBee2 and SD card installed
  • Both ND/ND+ share common XBee drivers codebase (All XBee and serial port code is shared)
  • I have tried hardware flow control on both ND/ND+ and is enabled on XBee.
  • (As a footnote, CTS never de-asserts on either XBee, it always remains low, and never goes low on ND)
  • I have SerialErrorReceivedEventHandler enabled, and it never fires.
  • Everything is running at 9600 baud, 8N1. (I want to try faster speeds to see if that makes a difference, but CTS flow control should handle buffering data for me?)

Attached is a far-away view of the data in the LA. The left side is showing the modem setup exchange, and the right side is showing the data packets: you can see the packeting leaving one XBee and arriving at the other… These are two messages with 200 byte packages.

Also attaching a zoomed in view to compare with what I am reading out of the Serial Port buffer.

Here is the code that is reading the buffer. Fairly simple. Called by the SerialDataReceivedEventHandler event:
private void Serial_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {

            //One at a time please....
            lock (readLock)
            {
                Debug.Print("Read unlocked with " + SerialPort.BytesToRead + " bytes to read");

                //FIXIT - May not need, but for some reason the event fires with nothing to read....
                int timeout = 100;
                while (SerialPort.BytesToRead <= 0 && timeout-- > 0) Thread.Sleep(10);

                byte[] buf = new byte[1];
                if (SerialPort.BytesToRead > 0)
                {
                    try
                    {
                        while (SerialPort.BytesToRead > 0)
                        {
                                
			   //If there is data, there is a incomplete frame, and we have a complete header
                            while ((SerialPort.BytesToRead > 0) && 
                                  (!frameBuilder.IsComplete) && 
                                  (frameBuilder.HeaderIsComplete)))
                            {
			       //Don’t forget about the checksum byte…  The + 1
                                byte[] buffer = new byte[frameBuilder.dataNeeded + 1];
                                //reading the data frame and the checksum byte
                                int bytesRead = SerialPort.Read(buffer, 0, frameBuilder.dataNeeded + 1);
                                Debug.Print("Read chunk of " + bytesRead.ToString() + " f: " + buffer[0].ToString() + " l: " + buffer[bytesRead-1].ToString() + " need " + (frameBuilder.dataNeeded + 1).ToString());
                                //Add the newly read data to the framBuilder buffer
                                frameBuilder.Append(buffer, bytesRead);
                            }
                            if (frameBuilder.IsComplete)
                            {
                                // got a frame, do something
                                ReceivedApiFrame(frameBuilder.GetApiFrame());
                                // Create a thread, launch fire event, etc
                                frameBuilder.Reset();
                            }
			    //Check to see is a header needs to be read (first three bytes)
                            if ((!frameBuilder.HeaderIsComplete) && (SerialPort.BytesToRead > 0))
                            {
                                SerialPort.Read(buf, 0, 1);
                                Debug.Print("Read byte for header " + buf[0].ToString());
                                frameBuilder.Append(buf, 1);
                            }
                            //Don't beat a hasty retreat after reading the frame…
                            timeout = 100;
                            while (SerialPort.BytesToRead <= 0 && timeout-- > 0) Thread.Sleep(10);
                        }
                    }
                    catch (Exception ex)
                    {
                        Debug.Print("Error reading data from serial " + ex.Message);
                    }
                }
                else Debug.Print("Nothing to read");//FIXIT – Get rid of this if() in production, ignore

                Debug.Print("Ending read " + local.ToString());
            }
        }

Here is the relevant Debug file to try and convince myself I am not going nuts... The data is really not there...

Read byte for header 126 <- good
Read byte for header 0 <- good
Read byte for header 212 <- good
Allocated 212 bytes to API Frame <- reading 200 bytes plus Zigbee frame
Read chunk of 16 f: 144 l: 52 need 213 <- extra room for checksum byte
Read chunk of 16 f: 34 l: 109 need 197
Read chunk of 15 f: 101 l: 109 need 181
Read chunk of 14 f: 32 l: 50 need 166
Read chunk of 15 f: 48 l: 87 need 152
Read chunk of 15 f: 97 l: 100 need 137
Read chunk of 14 f: 60 l: 48 need 122
Read chunk of 15 f: 54 l: 48 need 108
Read chunk of 15 f: 58 l: 99 need 93
Read chunk of 14 f: 114 l: 100 need 78
Read chunk of 15 f: 97 l: 49 need 64
Read chunk of 14 f: 32 l: 97 need 49
Read chunk of 15 f: 114 l: 105 need 35
Read chunk of 17 f: 99 l: 100 need 20
Read chunk of 3 f: 97 l: 110 need 3 <- finished, without checksum error!
Resetting frame
Staring processing thread… <- thread off to process the packet
(Here is where it goes horribly wrong….)
Read byte for header 126 <- good, found header start byte
Read byte for header 162 <- BAD! This is NOT a valid high-byte length
Error in length: 162
Resetting frame
Read byte for header 0
ERROR!!! Expected start byte: 0
Read byte for header 64
ERROR!!! Expected start byte: 64
Read byte for header 141
ERROR!!! Expected start byte: 141
Read byte for header 28
ERROR!!! Expected start byte: 28
Read byte for header 195
ERROR!!! Expected start byte: 195


The serial buffer contained the following bytes: (Refer to the attached LA image)
126(~), 162, 0, 64(@), 141, 28, 195…
But the XBee sent the following to the ND:
126(~), 0, 212, 144, 0, 19, 162, 0, 64(@), 141, 28, 195…
MISSING BYTES

Any ideas are welcome. I need to get some sleep!

Attached Thumbnails

  • Analyzer.jpg
  • Data.jpg



#33454 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 11 August 2012 - 08:43 PM in Beta Firmware and Drivers

Chris:
Thanks for the feedback. Here is how I spent my morning.

I used one ND with COM1 hooked to COM2 and got exactly the same results. All works fine as long as I can read the data fast enough. If not, there are very unpredictable results including crashing the ND. If I use any type of handshake; all bets are off and data is lost. I will eagerly await the RC6 build and re-test.

(I have not ported this back to 4.1 to see what happens there, that would require reflashing my NDs. and I am basically lazy that way! :) )


Here is another very peculiar thing related to serial ports. I posted about this in an earlier thread concerning 'System.InvalidOperationException' in the 'System.IO.Ports.SerialPort.HandlePinReservations' call. I am wondering if my 4.2 implementation is FUBAR? Here is the scenario:

Running a simple test application:
using System.IO.Ports;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using SecretLabs.NETMF.Hardware.Netduino;


namespace NetduinoApplication2
{
    public class Program
    {
        public class netduino
        {
            //Changing from const to static causes the sp.Open() method to throw a 'System.InvalidOperationException' Exception
            public const Cpu.Pin SomePin = Pins.GPIO_PIN_A4;
            //public static Cpu.Pin SomePin = Pins.GPIO_PIN_A4;
            public InterruptPort SomeInterrupt = new InterruptPort(SomePin, true, Port.ResistorMode.Disabled, Port.InterruptMode.InterruptEdgeBoth);
        }

        protected static netduino MCU = new netduino();

        public static void Main()
        {
            SerialPort sp = new SerialPort("COM2", 9600, Parity.None, 8, StopBits.One);
            sp.Open();
            Debug.Print("finished OK!");
        }
    }
}

Notice the definition for SomePin. If I define SomePin as static, the debug trace looks like this on the sp.Open() call:
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.Open'
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.Open'
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.HandlePinReservations'
Step into: Stepping over non-user code 'Microsoft.SPOT.Hardware.HardwareProvider.HwProvider.get'
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.HandlePinReservations'
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.HandlePinReservations'
A first chance exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.dll
Step into: Stepping over non-user code 'System.IO.Ports.SerialPort.HandlePinReservations'
A first chance exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll
An unhandled exception of type 'System.InvalidOperationException' occurred in Microsoft.SPOT.Hardware.SerialPort.dll

If I define as a const, all is good and no exception.

Not to make this even more confusing, but when I run the debugger and step through the code, when I get to the call for 'HandlePinReservations' I get a dialog box asking me to locate the following file:
C:\Documents\Secret Labs\Projects\Production\SecretLabs.NETMF.Hardware.Netduino\NetduinoHardwareProvider.cs (See attachment SourceScreen.jpg)

Any ideas on what is going on and where I might go next? The loss of data part is really the troubling part. I need to have an effective handshake so I can read and process larger chunks of data.

Attached Thumbnails

  • Source Screen.JPG



#33881 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 18 August 2012 - 10:43 PM in Beta Firmware and Drivers

Arbiter: When I do that, all works well. I am trying to abstract the hardware later from the rest of my code. I need to know what pin was used later because I share interrupts and what to know which pin caused the interrupt.



#33347 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 10 August 2012 - 02:28 AM in Beta Firmware and Drivers

HI AxelG,


Can you post a small repro app for us to look at? Generally speaking, NETMF 4.1 code should run as-is under NETMF 4.2.

Chris


I wound up flashing my ND+ to 4.2 anyway and noticed a couple things:
1) My USB is a lot more stable - no more BSODs (I also removed a bluetooth driver that may have been causing problems)
2) The extra code space is nice! Thanks.
3) I am seeing strange behavior with the Serial Port - losing data. (Posting a separate thread)
4) The COM2 problem went away (ArgumentOutOfRange no longer happens when opening the COM port.



#33447 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 11 August 2012 - 03:54 PM in Beta Firmware and Drivers

Hi AxelG,

Just to confirm... You're connecting two Netduinos together and are using flow control...and are losing data?


Yes, that is the scenario. Using no flow control works well as long as I can read data fast enough. I am going to play with various baud rates and see what changes.

If that's the scenario, does the same thing happen when you connect two serial ports together on one Netduino?

I will try that.


P.S. RC6 should be shipping in a few days. There is a serial port bugfix that recently made it into the NETMF core...so we may want to hold off digging in for a few days and see if the bugfix is related.

Cool. I will try that as well.



#33377 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 10 August 2012 - 03:54 PM in Beta Firmware and Drivers

Testing scenario for Serial Ports in 4.2 RC5

Scenario:
  • Hooked up a ND to ND+ on COM2 (TX to RX)
  • ND was sender, ND+ was reader
  • ND had no flow control, ND+ was set to Handshake.RequestToSend
  • Logic Analyzer was hooked to RX, TX and RTS/CTS pins on ND+
  • Wrote two applications, Reader and Sender (Projects.zip)
  • Sender running on ND sends 200 byte packages to reader running on ND+
  • Reader reads the 200 byte blocks and reports on whether it got all of the data.

Outcome:
  • Handshake.RequestToSend seems to have no affect on the hardware.
  • Sending the data slowly enough for the reader to stay caught up with the writer works fine.
  • When the reader goes off to do something else (simulated by a Thread.Sleep()) the SerialPort.Read() method throws “System.ArgumentException” (Debug 2.txt)
  • If the writer sends data to the buffer (SerialPort.Write() method) too fast, the “SerialErrorReceivedEventHandler” handler fires with “SerialError.TXFull”
One Solution Idea:
  • Use XON/XOFF flow control.
  • Set no delay in reading the data.
  • Set one second delay between sending packages.
Outcome:
  • Lost data. Reading the packages as fast as possible shows lost data (Debug 3.txt) This happens even when sending data in 200 byte packages with a delay between packages.
  • Turning off flow control, fixes the problem at slow speeds, until you set a read delay which causes data loss.

Any ideas on how I can send large blocks of data without losing bytes?

Attached Thumbnails

  • LA Failure.jpg

Attached Files




#33161 Netduino Firmware v4.2.0 RC5 (Netduino + Netduino Plus)

Posted by AxelG on 06 August 2012 - 12:30 PM in Beta Firmware and Drivers

HI AxelG,


Can you post a small repro app for us to look at? Generally speaking, NETMF 4.1 code should run as-is under NETMF 4.2.

Chris


I will try to later this week, but this is part of a larger program and I will need to create a smaller app to reproduce. Basically, I am defining the port, then assigning some interrupts and event handlers, and then opening the port - which is where I get this failure; but only on COM2. COM1 works fine...

I was also dealing with BSODs yesterday and just decided to update all my NDs to 4.2. That helped a lot; but still getting them on reboots.



#43717 Multithreading and writing to SD card

Posted by AxelG on 19 January 2013 - 01:16 AM in Netduino Plus 2 (and Netduino Plus 1)

I have written a couple applications that have multiple threads accessing the SD card at the same time; it works but you need to be careful with a couple things.  You hit on the first one; one thread per file (reading and writing).  If you need two threads, simple locking mechanism can ensure read/seek/write transactions remain pure.  Since each thread keeps their own file structures (Assuming you are not sharing them!); mostly you are OK.

 

I have also found that dealing with the SD card is quite resource intensive; especially when mixed with time-sensitive sensor reading.  It is easy to create bottlenecks in the code that create data flow problems. Multi-threading on the netduino is not parallel processing; it just allows you to branch execution into separate places in your code - processor time is shared between the threads so only one instruction is running at a time.  The right locking scheme can make all of the difference.

 

SD cards also use SPI.  This is another area to make sure you code is aware there are multiple SPI devices.





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