XBee Networks of Mayfly Loggers – 900Mhz

I just did a long post about this – but then when I completed I have been logged out somehow the post was lost. ouch.
Will try and reconstruct the post but got to get some other things done.
Neil

Nowadays you can buy dedicated base station modules that do the same thing as my homemade version, but almost 6 years ago when I first built it, there were very few reliable and affordable options.

The 900MHZ Xbee radios have a much better range in our forested terrain than the 2.4GHZ radios. In open and relatively flat areas, I’ve gotten almost a mile of distance between the logger and the base station. Your results will vary depending on the gain and placement of your antennas, and probably more importantly the topography and forest density. In terms of battery usage, they are very efficient when compared to the cellular modules we use in the hundreds of areas where we don’t have a base station. The radios sleep constantly just like the loggers, and when it’s time for a transmission, they are powered for a fraction of a second and then return to sleep.

I use both the RPSMA modules as well as the U.FL models, depending on what sort of enclosure I’m mounting the Mayfly in.
I use weatherproof bulkhead RPSMA fittings that mount the antenna on the enclosure, and sometimes they are a continuous, 1-piece design with a u.fl connector on the inside end. It also depends on how much physical abuse the radio module is going to see. The RPSMA fittings are much more appropriate if you’ll be moving the board or cables around frequently, since the u.fl connectors are somewhat fragile and finicky, and will fail quickly if you make-break the connection too many times.

The wire protocol used a TinyOS packet structure which could support a mesh. For a mesh the power usage and network maintenance considerations get more complicated.
The multi-point was a “gateway” that was at buildings that had power and internet access. So from the building antenna position the Line Of Sight for a standard XBP-900HP is about 9miles in a radius from that point – and can support 16bit addressing (65K) end point nodes.
In one location there was a slight ground hump in the way and it was on the edge of the range. I made sure the RSSI was part of the reported signal to be able to monitor it.
There are websites out there that can analyze elevation profile between two points to determine if there is an LOS.

Now-days I’m looking at a PocketBeagle with a Ethernet module and POE splitter
PocketBeagle-SC-569
MIKROE-971

I personally have found PoE 802.15af has worked very well for “borrowing” some space on some other entities building.
It has meant a long drill for going through an insulated wall, and physical access to the network somewhere in the building. Building maintenance is used to being helpful. It has been easier than IT WiFi access that is nervous about network breaches, and changing passwords.

I’m working with @dartmouthwsn, the original poster on this thread, to construct a logger network using Mayflys and 900 Mhz XBee Pros. We had the code successfully working so that the

I’m working with @dartmouthwsn, the original poster on this thread, to construct a logger network using Mayflys and 900 Mhz XBee Pros. We had the code successfully working so that the logger Mayflys were able to send data to a centrally located node using the Xbee Pros. The code has been functional for several months and was tested at several sites over varying distances with dependable and consistent results.

However, about a week ago, we ran into an issue with the code. The central Mayfly node receiving the data no longer consistently writes the data to its SD card or prints it to the serial. I’ve tried using different Mayflys as well as resetting the Mayflys. Though the code has gone through many iterations, even the original working code no longer functions for the receiving node.

Oddly enough, changing the baud rate of the XBee receiving data seems to work for a few uploads of the code––after changing the baud rate, the data is successfully collected for about three or four uploads of the code and then suddenly stops working again. Looking at the XBee’s serial in XCTU, I can see that all of the data is actually being received by the XBee, but not written to the SD card.

As far as I can tell, I think the issue is that, for some reason, the XBee serial is not recognized as being available despite the fact that the XBee is receiving data. I’ve tried re-downloading the libraries, thinking that my SoftwareSerial library may have been out-of-date, but nothing seems to fix the issue.

I’m wondering if anyone has run into a similar problem, and if anyone has any advice on how to solve the issue.
Any help would be greatly appreciated!

Emma

I am part of the Little Manistee Watershed Conservation Council here in North West Michigan. We are in the early stages of implementing a series of up to six monitoring stations alon

I am part of the Little Manistee Watershed Conservation Council here in North West Michigan. We are in the early stages of implementing a series of up to six monitoring stations along 72 river miles on the Little Manistee River. All stations will have CTD and at least one will have a Turbidity sensor. This conversation caught my attention because cell coverage in this area is very unreliable and I believe to make the Mayfly stations upload reliably the only choice is the xbee radio and not cell.

My plan for the first unit is to use xbee radio from the monitoring station to a base station in my house that will connect to the internet via an ethernet connection to my router and satellite. I expect the satellite system to be problematic, but it is my only choice here in the forest. The future additional units will either use the same configuration at other citizen scientists homes or connect as second or third nodes to existing base stations.

I am in the process of purchasing materials for the first unit. I was hoping for suggestions on the base station configuration and the radio modules.

For the base station it would appear an Uno with Ethernet and Xbee shields would serve the purpose with some programming. The Arduino Ethernet Shannon refers to in the link above shows it is retired with no newer version I can find. I have not been able to find a better alternative and am wondering if any of you have?

There are so many xbee radio modules out there it is overwhelming. We are in dense pine and oak forest and the monitoring stations will be in river valleys so the 900 MHZ xbee modules with external antennas are probably the place to start. Some monitors will be close to base stations, others will not. From reading the conversation above it sounds like I should use a non programmable radio module. Can any of you tell me what specific modules you have had success with and other parameters I should be considering based on your experience?

I feel like it’s an ordering issue in the loop() from when I updated the code, but I’m not sure. Any help is greatly appreciated! Thanks!

Also, while I’m here, I also have been struggling on how to take the sensor measurements that are printed to the SD card and communicate them to the Xbee (with the Serial1.println() line in the loop() command). I’m pretty new to Arduino programming, so I feel like I’m probably overcomplicating it.

/** =========================================================================
* @file DRWI_NoCellular.ino
* @brief Example for DRWI CitSci without cellular service.
*
* @author Sara Geleskie Damiano <sdamiano@stroudcenter.org>
* @copyright (c) 2017-2020 Stroud Water Research Center (SWRC)
* and the EnviroDIY Development Team
* This example is published under the BSD-3 license.
*
* Build Environment: Visual Studios Code with PlatformIO
* Hardware Platform: EnviroDIY Mayfly Arduino Datalogger
*
* DISCLAIMER:
* THIS CODE IS PROVIDED “AS IS” – NO WARRANTY IS GIVEN.
* ======================================================================= */

// ==========================================================================
// Include the libraries required for any data logger
// ==========================================================================
/** Start [includes] */
// The Arduino library is needed for every Arduino program.
#include <Arduino.h>

// EnableInterrupt is used by ModularSensors for external and pin change
// interrupts and must be explicitly included in the main program.
#include <EnableInterrupt.h>

// To get all of the base classes for ModularSensors, include LoggerBase.
// NOTE: Individual sensor definitions must be included separately.
#include <LoggerBase.h>
/** End [includes] */

//Defines the XBEE Sleep pin
#define XBEE_SleepPin 23

// ==========================================================================
// Data Logging Options
// ==========================================================================
/** Start [logging_options] */
// The name of this program file
const char* sketchName = “sensor_test.ino”;
// Logger ID, also becomes the prefix for the name of the data file on SD card
const char* LoggerID = “XXXXX”;
// How frequently (in minutes) to log data
const uint8_t loggingInterval = 1;
// Your logger’s timezone.
const int8_t timeZone = -5; // Eastern Standard Time
// NOTE: Daylight savings time will not be applied! Please use standard time!

// Set the input and output pins for the logger
// NOTE: Use -1 for pins that do not apply
const int32_t serialBaud = 115200; // Baud rate for debugging
const int8_t greenLED = 8; // Pin for the green LED
const int8_t redLED = 9; // Pin for the red LED
const int8_t buttonPin = 21; // Pin for debugging mode (ie, button pin)
const int8_t wakePin = A7; // MCU interrupt/alarm pin to wake from sleep
// Set the wake pin to -1 if you do not want the main processor to sleep.
// In a SAMD system where you are using the built-in rtc, set wakePin to 1
const int8_t sdCardPwrPin = -1; // MCU SD card power pin
const int8_t sdCardSSPin = 12; // SD card chip select/slave select pin
const int8_t sensorPowerPin = 22; // MCU pin controlling main sensor power
/** End [logging_options] */

// ==========================================================================
// Using the Processor as a Sensor
// ==========================================================================
/** Start [processor_sensor] */
#include <sensors/ProcessorStats.h>

// Create the main processor chip “sensor” – for general metadata
const char* mcuBoardVersion = “v0.5b”;
ProcessorStats mcuBoard(mcuBoardVersion);
/** End [processor_sensor] */

// ==========================================================================
// Maxim DS3231 RTC (Real Time Clock)
// ==========================================================================
/** Start [ds3231] */
#include <sensors/MaximDS3231.h>

// Create a DS3231 sensor object
MaximDS3231 ds3231(1);
/** End [ds3231] */

// ==========================================================================
// Campbell OBS 3 / OBS 3+ Analog Turbidity Sensor
// ==========================================================================
/** Start [obs3] */
#include <sensors/CampbellOBS3.h>

const int8_t OBS3Power = sensorPowerPin; // Power pin (-1 if unconnected)
const uint8_t OBS3NumberReadings = 10;
const uint8_t ADSi2c_addr = 0x48; // The I2C address of the ADS1115 ADC
// Campbell OBS 3+ *Low* Range Calibration in Volts
const int8_t OBSLowADSChannel = 0; // ADS channel for *low* range output
const float OBSLow_A = 0.000E+00; // “A” value (X^2) [*low* range]
const float OBSLow_B = 1.000E+00; // “B” value (X) [*low* range]
const float OBSLow_C = 0.000E+00; // “C” value [*low* range]

// Create a Campbell OBS3+ *low* range sensor object
CampbellOBS3 osb3low(OBS3Power, OBSLowADSChannel, OBSLow_A, OBSLow_B, OBSLow_C,
ADSi2c_addr, OBS3NumberReadings);

// Campbell OBS 3+ *High* Range Calibration in Volts
const int8_t OBSHighADSChannel = 1; // ADS channel for *high* range output
const float OBSHigh_A = 0.000E+00; // “A” value (X^2) [*high* range]
const float OBSHigh_B = 1.000E+00; // “B” value (X) [*high* range]
const float OBSHigh_C = 0.000E+00; // “C” value [*high* range]

// Create a Campbell OBS3+ *high* range sensor object
CampbellOBS3 osb3high(OBS3Power, OBSHighADSChannel, OBSHigh_A, OBSHigh_B,
OBSHigh_C, ADSi2c_addr, OBS3NumberReadings);
/** End [obs3] */

// ==========================================================================
// Meter Hydros 21 Conductivity, Temperature, and Depth Sensor
// ==========================================================================
/** Start [decagon_ctd] */
#include <sensors/DecagonCTD.h>

const char* CTDSDI12address = “1”; // The SDI-12 Address of the CTD
const uint8_t CTDNumberReadings = 6; // The number of readings to average
const int8_t SDI12Power = sensorPowerPin; // Power pin (-1 if unconnected)
const int8_t SDI12Data = 7; // The SDI12 data pin

// Create a Decagon CTD sensor object
DecagonCTD ctd(*CTDSDI12address, SDI12Power, SDI12Data, CTDNumberReadings);
/** End [decagon_ctd] */

// ==========================================================================
// Creating the Variable Array[s] and Filling with Variable Objects
// ==========================================================================
/** Start [variable_arrays] */
Variable* variableList[] = {
new DecagonCTD_Cond(&ctd),
new DecagonCTD_Temp(&ctd),
new DecagonCTD_Depth(&ctd),
new CampbellOBS3_Turbidity(&osb3low, “”, “TurbLow”),
new CampbellOBS3_Turbidity(&osb3high, “”, “TurbHigh”),
new ProcessorStats_Battery(&mcuBoard),
new MaximDS3231_Temp(&ds3231),
};

// All UUID’s, device registration, and sampling feature information can be
// pasted directly from Monitor My Watershed. To get the list, click the “View
// token UUID list” button on the upper right of the site page.
// Even if not publishing live data, this is needed so the logger file will be
// “drag-and-drop” ready for manual upload to the portal.

// *** CAUTION — CAUTION — CAUTION — CAUTION — CAUTION ***
// Check the order of your variables in the variable list!!!
// Be VERY certain that they match the order of your UUID’s!
// Rearrange the variables in the variable list if necessary to match!
// *** CAUTION — CAUTION — CAUTION — CAUTION — CAUTION ***
const char* UUIDs[] = {
“12345678-abcd-1234-ef00-1234567890ab”, // Electrical conductivity
// (Decagon_CTD-10_Cond)
“12345678-abcd-1234-ef00-1234567890ab”, // Temperature
// (Decagon_CTD-10_Temp)
“12345678-abcd-1234-ef00-1234567890ab”, // Water depth
// (Decagon_CTD-10_Depth)
“12345678-abcd-1234-ef00-1234567890ab”, // Turbidity (Campbell_OBS3_Turb)
“12345678-abcd-1234-ef00-1234567890ab”, // Turbidity (Campbell_OBS3_Turb)
“12345678-abcd-1234-ef00-1234567890ab”, // Battery voltage
// (EnviroDIY_Mayfly_Batt)
“12345678-abcd-1234-ef00-1234567890ab” // Temperature
// (EnviroDIY_Mayfly_Temp)
};
const char* registrationToken =
“12345678-abcd-1234-ef00-1234567890ab”; // Device registration token
const char* samplingFeature =
“12345678-abcd-1234-ef00-1234567890ab”; // Sampling feature UUID

// Count up the number of pointers in the array
int variableCount = sizeof(variableList) / sizeof(variableList[0]);

// Create the VariableArray object
VariableArray varArray(variableCount, variableList, UUIDs);
/** End [variable_arrays] */

// ==========================================================================
// The Logger Object[s]
// ==========================================================================
/** Start [loggers] */
// Create a new logger instance
Logger dataLogger(LoggerID, loggingInterval, &varArray);
/** End [loggers] */

// ==========================================================================
// Working Functions
// ==========================================================================
/** Start [working_functions] */
// Flashes the LED’s on the primary board
void greenredflash(uint8_t numFlash = 4, uint8_t rate = 75) {
for (uint8_t i = 0; i < numFlash; i++) {
digitalWrite(greenLED, HIGH);
digitalWrite(redLED, LOW);
delay(rate);
digitalWrite(greenLED, LOW);
digitalWrite(redLED, HIGH);
delay(rate);
}
digitalWrite(redLED, LOW);
}

// Reads the battery voltage
// NOTE: This will actually return the battery level from the previous update!
float getBatteryVoltage() {
if (mcuBoard.sensorValues[0] == -9999) mcuBoard.update();
return mcuBoard.sensorValues[0];
}
/** End [working_functions] */

// ==========================================================================
// Arduino Setup Function
// ==========================================================================
/** Start [setup] */
void setup() {
// Start the primary serial connection
Serial.begin(serialBaud);

//Sets up the baud rate for the XBEE
Serial1.begin(9600);

// Print a start-up note to the first serial port
Serial.print(F(“Now running “));
Serial.print(sketchName);
Serial.print(F(” on Logger “));
Serial.println(LoggerID);
Serial.println();

Serial.print(F(“Using ModularSensors Library version “));
Serial.println(MODULAR_SENSORS_VERSION);

// Set up pins for the LED’s
pinMode(greenLED, OUTPUT);
digitalWrite(greenLED, LOW);
pinMode(redLED, OUTPUT);
digitalWrite(redLED, LOW);

//Sets up pins for the XBEE
pinMode(XBEE_SleepPin,OUTPUT); //Setting XBEE sleep pin as an output
digitalWrite(XBEE_SleepPin, LOW); //Start with XBEE awake
Serial.println(“Xbee is now set up”);
delay(2000);

// Blink the LEDs to show the board is on and starting up
greenredflash();

// Set the timezones for the logger/data and the RTC
// Logging in the given time zone
Logger::setLoggerTimeZone(timeZone);
// It is STRONGLY RECOMMENDED that you set the RTC to be in UTC (UTC+0)
Logger::setRTCTimeZone(0);

// Attach information pins to the logger
dataLogger.setLoggerPins(wakePin, sdCardSSPin, sdCardPwrPin, buttonPin,
greenLED);
dataLogger.setSamplingFeatureUUID(samplingFeature);

// Begin the logger
dataLogger.begin();

// Note: Please change these battery voltages to match your battery
// Set up the sensors, except at lowest battery level
if (getBatteryVoltage() > 3.4) {
Serial.println(F(“Setting up sensors…”));
varArray.setupSensors();
}

// Create the log file, adding the default header to it
// Do this last so we have the best chance of getting the time correct and
// all sensor names correct
// Writing to the SD card can be power intensive, so if we’re skipping
// the sensor setup we’ll skip this too.
if (getBatteryVoltage() > 3.4) {
Serial.println(F(“Setting up file on SD card”));
dataLogger.turnOnSDcard(
true); // true = wait for card to settle after power up
dataLogger.createLogFile(true); // true = write a new header
dataLogger.turnOffSDcard(
true); // true = wait for internal housekeeping after write
}

// Call the processor sleep
Serial.println(F(“Putting processor to sleep\n”));
dataLogger.systemSleep();
}
/** End [setup] */

// ==========================================================================
// Arduino Loop Function
// ==========================================================================
/** Start [loop] */
// Use this short loop for simple data logging and sending
void loop() {
// Note: Please change these battery voltages to match your battery
// At very low battery, just go back to sleep
if (getBatteryVoltage() < 3.4) {
dataLogger.systemSleep();
}
// If the battery is OK, log data
else {
wakeXbee(); //Wakes up XBEE
delay(3000); //Gives XBEE time to be seen by the network
Serial1.println(); //Text being sent by XBEE module
delay(3000); //Gives XBEE a bit before sending it back to sleep
sleepXbee(); //Puts Xbee to sleep

delay(10000); //wait 10 seconds, then repeat loop
dataLogger.logData();

}
}

void sleepXbee() {
Serial.println(“Putting the Xbee to sleep”);
delay(100);
pinMode(XBEE_SleepPin,INPUT_PULLUP); // Set the “wake-up pin” to input and enable the internal pullup
digitalWrite(XBEE_SleepPin,HIGH); //put the Xbee to sleep
digitalWrite(9, LOW); //turn off the RED LED when the Xbee is asleep
}

void wakeXbee() {
Serial.println(“Wake up the Xbee”);
delay(100);
pinMode(XBEE_SleepPin,OUTPUT); // Set the “wake-up pin” to output
digitalWrite(XBEE_SleepPin,LOW); // wake-up XBee
digitalWrite(9, HIGH); // turn on the RED LED when the Xbee is awake
}
/** End [loop] */

Right now I am just trying to get two Mayflies to send/receive temperature measurements from the Mayfly’s built-in temperature sensor. This first bit of code is for the Mayfly making the measurement and sending the data. The green LED (pin 8) is just so I can easily tell that the Mayfly is running the loop when I have it plugged into a wall.

This next bit of code is for the Mayfly receiving the data and then printing it to the serial monitor so that I can verify that it is indeed receiving the data.

Right now my serial monitor just prints out a bunch of -1 values. Any help is appreciated. Thanks!

Seems you are thinking of using it in a Peer-2-peer arrangement, possibly in a mesh configuration. A

Seems you are thinking of using it in a Peer-2-peer arrangement, possibly in a mesh configuration. A lot of options.

I wonder what your back ground is  – cause its sort of like jumping into the deep end, and you may wanna flesh out your plan – what your basic intent is.  Is there any reason XBee Pro S3B, and not a LoRa in a peer to peer? (Digi XBee LR).

From what I remember, for some of the Xbee’s you can configure in a point to point mode, and then it looks like you are sending data down a wire. The critical issue is that through the XCTU you configure two units to look like a wire  – start with XCTU and data sheet of the devices.  Of course if you are sending in JSON one end , then you need to have a JSON parser the other end. So that means you want to design your JSON packet. Of course JSON is bulky and thats where if you use the simplest binary numbers, it could fit in a LoRa packet, thats why I bring up the differences.

I’d suggest looking at how to interface to the Campbell Scientific – that is can you inject some dimension less numbers in some fashion and have it come out the other side somewhere that can be used.  Maybe other people know more about it, than I do – but you may want the specific model numbers.  I looked at trying to work with a 20yr old CS recently, and concluded it really needed a whole new upgrade  – and actually finding the satellite channels for even an upgrade  was going to be one challenge.

At the simplest level, if you have some Analog inputs available on the Campbell scientific, then it could be case of “extending” those inputs remotely, and scaling the input voltage to your snow depth units.

So then on the snow depth sensor,  how does the sensor present its measurement   – from other posts on the board it seems you are trying to measure some voltages, so may be that is the snow depth measurement.  So then what is the range of the depth measurement. you want to make and what is the dynamic range and resolution on the sensor. That is the sensor might have a dynamic range of 3meter with an accuracy of +/10cm, but actually you are only interested in if there is 0-5cm increase of snow in a 1hour period.

Maybe some other people have better insights – but that would be my first guess at defining what you want to achieve

You would have to set up your radio using the

You would have to set up your radio using the Digi software and then write your loop function, which would print your json or csv string out over the serial port for the radio to hear.

What it sounds like you are asking is can

What it sounds like you are asking is can two S3Bs be setup like a “wire” – a link for two S3Bs – a peer-two-peer (P2P) link.
That is “print”  an ASCII serial string to an S3B over the UART and have it come out another S3B uart.

I am afraid its looking at the manual to see if this can be done for the particular model, and follow the examples they give in the manual.

Like a vehicle – for exact technical capabilities dig into the manual

I know some of the 900Mhz models I looked at could do it. However, as its wireless also look at under what conditions it might loose parts the string Good luck.

A vehicle represents a number of parts  that hang together ~ ModularSensors represents a number of Classes that hang together – the value of open source is you can modify the programs/Classes.

However that implies you’ve launched off on your own – so phrasing your question right, 🙂  becomes something you are trying to refine?.

Based on your previous application environment, It seems like you might be asking, “how do I receive the data on Mayfly2 and push it to the .csv file?”