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MayFly Capability with Northern Widget Walrus Sensor

Home Forums Environmental Sensors MayFly Capability with Northern Widget Walrus Sensor

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    • #14726
      Tom Schanandore
      Participant
        Hello,

        I have been working a company called Northern Widget out of St. Paul Minnesota regarding their water pressure sensor named the Walrus. It is connected via. a I2C port and they say it should wo

      • #14727
        Sara Damiano
        Moderator
          Bobby Shultz or Northern Widget did some of the work to incorporate the MPL115A into ModularSensors, but I haven’t followed what they’ve been doing.

          It looks like this Walrus thing has an

        • #14728
          Tom Schanandore
          Participant
            Thanks Sara,

            I have been working with Bobby and Andy Wickert over there on this and they gave me sensors with the appropriate firmware installed already. I did not have to install any firmware. It wa

          • #14729
            Sara Damiano
            Moderator

              Someone has to dig through their firmware file and reverse engineer the communication protocol.

            • #14730
              Tom Schanandore
              Participant
                Honestly my understanding of all this is pretty basic, but I understand that the firmware is very important. I left it up to Northern Widget to upload the appropriate firmware to the sensor before the
              • #14731
                Sara Damiano
                Moderator
                  I2C and RS485 are two different communication protocols.  They specify what change marks a 1 or a 0 when transferring information.  I2C also (mostly) specifies the question-and-answer format.  So k
                • #14732
                  Tom Schanandore
                  Participant
                    I am assuming that the firmware also has something to do with making the sensor signal work over the length of the 3m cable? The sensor does work when attached directing to the I2C port (via. grove ca
                  • #14733
                    Sara Damiano
                    Moderator
                      WRT to the wire distance, yes and no.

                      RS485 is a two-wire protocol where 0’s and 1’s are differentiated by the difference in voltage between the two wires.  Electrically, this means it c

                    • #14734
                      Sara Damiano
                      Moderator

                        I’m sorry, I’m looking through their firmware and trying to figure something out for you.  I hate half-answering a question.

                      • #14735
                        Sara Damiano
                        Moderator

                          post deleted

                        • #14736
                          Tom Schanandore
                          Participant
                            Much appreciated. There are a few trouble shooting things that I did that may be difficult to explain over the forum. If you would like to discuss my phone is 701-390-2040. These trouble shooting thin
                          • #14737
                            Tom Schanandore
                            Participant
                              I only paid for the one, which was not housed. That one I will keep. The other four they just sent, without first figuring out the problem. If they don’t work I will simply send the four back. Y
                            • #14739
                              Sara Damiano
                              Moderator
                                Alright, here’s something.  I can’t promise it *works*, but I’d like to see the results.

                              • #14740
                                Tom Schanandore
                                Participant

                                  I am assuming that this is a firmware to be uploaded to the sensor?

                                • #14741
                                  Sara Damiano
                                  Moderator

                                    No, no, that’s for a Mayfly talking to a sensor with the firmware Northern Widget posted on GitHub.

                                  • #14742
                                    Tom Schanandore
                                    Participant

                                      I see. Do I simply upload to the mayfly with the sensor attached? Or is this code to be added in somewhere in my overall code (PlatformIO)?

                                    • #14743
                                      Sara Damiano
                                      Moderator

                                        That’s the full code, you should upload it to the mayfly with the sensor powered and attached to the I2C on the Mayfly.  Then start a serial terminal at 9600 and you should see output.

                                      • #14744
                                        Tom Schanandore
                                        Participant

                                          I uploaded the code and the serial output is attached.

                                           

                                          Attachments:
                                        • #14746
                                          Tom Schanandore
                                          Participant

                                            It’s reading something, which is a lot better than before, as it read nothing before.

                                          • #14747
                                            Sara Damiano
                                            Moderator

                                              No, it’s just *printing* something.  I don’t think the sensor’s responding.

                                            • #14748
                                              Sara Damiano
                                              Moderator
                                                Ok, here’s new code for the Mayfly.  This should be much more verbose and show more clearly if the sensor’s responding.

                                              • #14749
                                                Sara Damiano
                                                Moderator

                                                  If (when) that fails, you can try an I2C scanner program on the Mayfly to see if the sensor has a different address.

                                                • #14750
                                                  Sara Damiano
                                                  Moderator
                                                    Also try flipping the SCL and SDA pins if you’re getting nothing.  Some versions of the Mayfly had them labeled backwards.

                                                    Also on a Mayfly you should always be finding a device at 0x48 and at

                                                  • #14751
                                                    Tom Schanandore
                                                    Participant

                                                      Ran the second bit of code and the scanner code. The scanner codes serial output is at the end.

                                                      See attached

                                                      Attachments:
                                                    • #14754
                                                      Sara Damiano
                                                      Moderator
                                                        So it is there and responding, but there’s something wrong with my code because it’s not giving data.  Do you know if the firmware on your device *is* that code on github?  Otherwise, I
                                                      • #14758
                                                        Sara Damiano
                                                        Moderator
                                                          I’m sorry; I’ve spent a lot of time reading through that firmware and if there’s something you have to do to get it to start taking readings, I don’t know what it is.  So eith
                                                        • #14759
                                                          Tom Schanandore
                                                          Participant

                                                            I will contact Northern Widget to see if they will send the firmware that they uploaded for verification on this end.

                                                          • #14760
                                                            Sara Damiano
                                                            Moderator
                                                              You don’t need the whole firmware; actually I’d prefer not to get the firmware, but instead to get a short breakdown of the required I2C registers and commands.  All I wo
                                                            • #14762
                                                              Tom Schanandore
                                                              Participant
                                                                See the link below to the firmware that they say is on the sensor. It is probably the same firmware you are looking at. I am requesting also the I2C registers and commands.

                                                                https://github.com/Norther

                                                              • #14763
                                                                Sara Damiano
                                                                Moderator
                                                                  That’s the firmware I’ve been looking at.

                                                                  You know what, I don’t think this firmware even functional.  It won’t ever take a sample.  Well, it should sample 1 time at the beg

                                                                • #14764
                                                                  Tom Schanandore
                                                                  Participant
                                                                    Is there anything strange about the fact that the walrus sensor does output good values when I have it connected directly (via grove connector) to the MayFly? And of course it is only when I connect i
                                                                    • #14765
                                                                      Sara Damiano
                                                                      Moderator
                                                                        Does it output good value*S* or one single good value over and over?  If the former, then..I just don’t know how to read this firmware.  If the latter, then, no that’s what I expect.

                                                                        3m

                                                                    • #14766
                                                                      Tom Schanandore
                                                                      Participant
                                                                        They are good values and slightly vary. I have verified the output with the MPL115A2 sensor that I have and the values are the same.

                                                                        They said that the 3m cable works great with their data loggers on

                                                                      • #14768
                                                                        Sara Damiano
                                                                        Moderator
                                                                          What code are you running to get the values?  The results you shared with me based on the code I gave you didn’t have any good values at all.  I thought you didn’t have any working code
                                                                        • #14769
                                                                          Tom Schanandore
                                                                          Participant
                                                                          • #14770
                                                                            Tom Schanandore
                                                                            Participant

                                                                              The previous is the code that they gave me to begin with. It does work when directly connected to the MayFly and Arduino Uno. IT does also work on the Arduino Uno (5v) when using the 3m cable.

                                                                            • #14772
                                                                              Sara Damiano
                                                                              Moderator

                                                                                You had a working library and code this whole time.

                                                                                ?!?

                                                                                Well I feel really, really stupid.

                                                                              • #14773
                                                                                Tom Schanandore
                                                                                Participant
                                                                                  I apologize for not saying that from the get go. My knowledge with all of this is rather limited, to be honest. I thought you were just trying to talk between the Sensor and the MayFly. The current li
                                                                                • #14774
                                                                                  Sara Damiano
                                                                                  Moderator
                                                                                    <!–more–>Yeah, so 99.99% of what I’ve said on this thread can be completely disregarded. Obviously the sensor and firmware work just fine and there never was any problem with t
                                                                                  • #14775
                                                                                    Tom Schanandore
                                                                                    Participant

                                                                                      So I think that I’m out of luck on this sensor, based upon what you just said. I’ll have to abandon this sensor.

                                                                                      thank you for all your help and sorry again for the miscommunication.

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