Shannon Hicks

The SIM808 module on the FONA must be powered directly from a 3.7v LiPo battery because it draws around 500mA during data operation, and can have occasional draw of up to 2 amps during a TX burst. The SIM808 module also requires a power source of 4.0v nominal, with a minimum of 3.4v and a max of 4.4v. So powering it directly from a 3.7v Lipo is…[Read more]

You don’t have to post the actual sketch here since it likely contains the unique URLs, registration tokens, and UUIDs that we’ve developed for transmitting the data to the online database portal. We can contact you directly through email to get the code and can then take a look at it to see what’s causing the instability. I have some ideas…[Read more]

Mayfly boards have been back in stock on Amazon since earlier this week. The starter kits should be available on Amazon next week.

What logging sketch was your Mayfly running? Was this a sketch that you wrote yourself, or is it one we provided to you with the board?

Depending on the browser you’re using, your save options might be worded differently in the drop down box when you right-click on a link. You could also just go directly to the library.zip file page: https://github.com/EnviroDIY/Libraries/blob/master/libraries.zip
and then click the gray “Download” button on the lower-right side of the page.…[Read more]

Because the v0.5 board can now accept an input supply voltage up to 12v, I had to change the onboard voltage divider that’s used for measuring the battery voltage by way of A6. So the formula for reading the battery voltage on a v0.3 or v0.4 board is this:

rawBattery = analogRead(A6);
sensorValue_battery = (3.3 / 1023.) * 1.47 * rawBattery;

But…[Read more]

Because the v0.5 board can now accept an input supply voltage up to 12v, I had to change the onboard voltage divider that’s used for measuring the battery voltage by way of A6. So the formula for reading the battery voltage on a v0.3 or v0.4 board is this:

rawBattery = analogRead(A6);
sensorValue_battery = (3.3 / 1023.) * 1.47 * rawBattery;

But…[Read more]

The Mayfly has 3 hardware interrupts. They are RXD1 (INT0), TXD1 (INT1), and D10 (INT2). To use the “attachInterrupt” function, you can only use the three hardware interrupt pins, and you have to refer to them as “0”, “1”, or “2”. So if you want to use the D10 interrupt pin, you’ll need to say the following on line 8:

attachInterrupt(2,…[Read more]

For anyone wondering about current Mayfly availability, I just received the shipment from the manufacturer today. I’ll be working to get them to Amazon by the end of the week. I sent in a bunch more of the protoshields today, next I’ll be sending lots of both the bare Mayfly boards and the starter kits.

Something I’m not seeing in your first sketch is where you declare what chipselect pin for the SD card. On the Mayfly it’s 12, so on line 42, change the “SS” to “12”. Then remove all the extra Serial.begin(9600) statements so there’s only one at the beginning of the setup function. And remove the RTC stuff on lines 11, 16, and 41. See if that…[Read more]

That’s a good question, thanks for asking: The new v0.5 board will handle an absolute maximum input voltage of 16v, so you should be okay. The 12v limit is the maximum “recommended” voltage. A charger for a 12v battery will output 13 or 14v, but it’s still safe to use that with the Mayfly (version 0.5 only). The older v0.3 and v0.4 boards get…[Read more]

The first couple things that stand out are this:

You don’t have to say “Serial.begin(9600)” more than once in your sketch. Just do it once near the beginning of your setup() function and that’s it.

You don’t have to set the date and time of the RTC every time you run the sketch. The way it is written in your examples means that the clock gets…[Read more]

I plotted the temperature and VWC on the same chart and you can see that they are very much linked together. Can you answer whether the sensor is completely buried in the soil, and if so how deep is it? If only the fiberglass tines are inserted into the soil but the rest of the sensor body is above ground and subjected to direct sunlight or…[Read more]

The graph looks more like a plot of temperature rather than VWC. Are you sure you’re plotting the right column of data? What are you using to actually record the data? Your sketch doesn’t output the data to a file or even print it in a easily-captured string out to the serial port, so I’m wondering how you collected multiple days of data. Plot…[Read more]

It would be helpful for you to attach a jpg of png image of your graph instead of a Powerpoint slide. You also can’t attach the raw .ino file to forum posts, but you can cut and paste it using the “code” tags in the post editor tools.

And on your graph, can you please label both the x and y-axis? I don’t know what parameter you’re graphing…[Read more]

Did you try running the PCsync.exe file on your computer with the Mayfly attached? That method worked for me last time I tried it. But I usually just use the adjust.ino sketch available in the Examples folder of the Sodaq_DS3231 library. Or you could use any DS3231 library since there’s nothing unique about the Mayfly’s RTC configuration.

I have confirmed that removing capacitor C4 will let the board continue to run without resetting when you open the serial monitor window. HOWEVER — This only works if you’re using the FTDI connector on the Mayfly (and a separate FTDI interface device like the Adafruit “FTDI Friend”) to connect it to your computer.

If you want to have this…[Read more]

The protoboards are now available on Amazon, via the URL I posted above. The Mayfly boards and the protoboards are selling fast, but we have a really big order of boards and accessories being assembled right now, so I hope to have the Amazon storefront fully stocked soon.