Tihs is my function to calculate voltage : voltage = 2.0 x 3.64 x measure / 4096.0 (=> 3.64 x measure / 2048 to avoid useless operations) So it looks like you came to almost the same thing. Where did you get this extra factor 1.10 (3.64 / 3.3) from? I can't find any reference to it, nor an explanat...

I moved the SC card initialisation part out of setup() into a function so it only gets loaded when needed. I also disabled Bluetooth and reclaimed its memory so now I am north of 220 kB free again. OTA works fine now. It would be nice to know the minimum required, though. And I still wonder about Se...

Yes, I have, but since I am not using 25 and 26 that way (interrupts), I didn't experience the issues you have. Can't you move those buttons to another pair of pins? Regarding measuring voltage: I have to use (analogRead(35) * 3.3 * 2.0 * 1.12) / 4095.0f 3.3: is normally the max voltage a pin can re...

I am building a weather station with all kinds of sensors, SD card etc. When the program is running it results in a reported free heap of only 114 kB. OTA does not work anymore but when I run the example BasicOTA, it works. The OTA code in my program is copy / paste from that example. Could it be th...