Shannon Hicks

The sample code above will not work properly until you’ve correctly changed the channel number for each of the 6 sensors. Also, once you do that and you have a different number of sensors other than 6, you’ll need to change the number in line 31 to the correct number of sensors.

So first you should make sure you change the channel number of one…[Read more]

It’s not currently available in Europe, but we’re working on it!

The circuit components are rated to the industrial temperature range of -40C to +85C, but I think at extreme temperatures you’re more likely to encounter problems with your battery rather than the Mayfly circuit. LiPo batteries don’t perform well at either really cold or really hot temperatures, so you might consider a different type of battery…[Read more]

Here’s some sample code for running 6 Decagon 5TM probes with a standard Uno board. It could be modified by changing the pin number for the LED, in the example below I used the default pin 13 for the onboard LED. Mayfly users would want to select either 8 or 9. I usually prefer to do long-time recording with a separate real-time-clock module…[Read more]

You’re going to need to connect the sensors one at a time to the Arduino board in order to program the address. Then you’ll need to hook them all together to the same bus. For example, all 6 of the sensor power wires need to go to the Vcc power bus, all 6 of the sensor ground wires need to go to the board GROUND, and all 6 of the sensor data…[Read more]

I’ve connected 15 of the Decagon 5TM sensors to one Mayfly board before, so it’s no problem to connect 6 to a Duemilanove. You’ll need to figure out how to get them all wired to the board, and that depends on what type of termination is on the ends of the sensors. Do your 5TM probes have the 3.5mm stereo headphone-type jack on the ends, or are…[Read more]

Did you use the “Address Change” example included with the SDI12 library to give each sensor a unique address? Decagon 5TM sensors are always set to default address “0” when you first use them, so you’ll need to select new ones. I’d suggest something sequential like 1, 2, 3, etc so that it’s easy to cycle through them in the sampling code. How…[Read more]

ArnoudC, the second half of the Ultrasonic sensor example now has sample code for recording the data to a memory card and also puts the logger to sleep between readings.

For anyone interested in putting their Mayfly to sleep between sensor readings, I recently posted this Sleeping Mayfly Logger example sketch:

Sleeping Mayfly logger example

Different types of SDI12 sensors have different commands for taking measurements and retrieving data from the sensor, so the Arduino code has to be modified for whatever specific sensor you’re using. Plus if you’re using multiple sensors, they each have to be pre-programmed with a unique address, which you then call separately in the Arduino…[Read more]

Neil, these were all good observations about the 5v boost circuitry on the Mayfly. The NCP1402 has been obsoleted by the manufacturer, so I’m looking for alternative ways to generate 5v and possibly other voltages onboard the Mayfly.

Yes, you could attach a 4.5v alkaline battery pack to the LIPO battery connection, but since you never know who might come along later and plug a solar panel into the SOLAR jack, it’s good practice to only connect LIPO batteries to that jack. That’s why I designed a separate 2-pin header (unpopulated) on the Mayfly that’s labeled “Ext 5V” so you…[Read more]

ChanCafun: that’s awesome, it looks really good. I assume you didn’t have any trouble figuring out the layout and spacing of the two 2×10 headers. I put them on a standard 0.1″ grid so it would be easy for people to produce their own accessory boards.

What SDI-12 sensors are you using? I don’t recognize those 6-pin connectors, but they look…[Read more]

ArnoudC, I’m not sure which Maxbotix sensor you’re using, but on the models we usually use, it’s pin 5 on the sensor that gets connected to the Mayfly digital pin (pin 5 in my example code above, but you can make it whatever you want). I think on most of the Maxbotix sensors, Pin 6 and 7 are the power and ground pins, and pin 5 is the serial TTL…[Read more]