Welcome to EnviroDIY, a community for do-it-yourself environmental science and monitoring. EnviroDIY is part of WikiWatershed, an initiative of Stroud Water Research Center designed to help people advance knowledge and stewardship of fresh water.
New to EnviroDIY? Start here

Reply To: Mayfly 1.1 Bootloader Burning?

Home Forums Mayfly Data Logger Mayfly 1.1 Bootloader Burning? Reply To: Mayfly 1.1 Bootloader Burning?


    That is useful, and along the lines of my thinking: moving to LiSOCL2. Though I am having trouble getting supplies to test. The internal impedance of those, especially when low or cold, is a big question to resolve. My system can use all the deep-sleep tricks, but when measuring the load averages ~50 mA with spikes up to ~350 mA for fractions of a second, and I wonder if this will cause a brown-out with the LiSOCL2 cells. Additionally, if I use these cells, we’ll need to use an array of 4, behind protection diodes, which drop the input voltage a bit, but also could provide more current during operation.

    I had not thought to try using a bigger buffer capacitor in front of the Mayfly. I got some more stability with 1000uF with my ammeter in the circuit, but some configurations still got resets: I figured that it was confusing the voltage regulator somehow, as I could not resolve a deep voltage sag on the inputs when measuring. I will look at the datasheet again and meditate.

    But if I could just set the brownout to 1.8V instead of 2.7V that would still be a nice test/check. I tried hooking up through the SD card vertical socket and the DTR pin of the FTDI connector, but wasn’t successful. I am wondering if the pin order in J7 is correct in the schematic, I can’t see the traces under the SD card slot on the PCB, so hoping that I can get clarity here, though I will probably just try to probe out the pins soon.