For all of you out there with Chinese NANO clones, or older Arduino NANO’s, there has been a recent change. The upload baud rate has been bumped up from 57600 to 115200, and that causes a upload error.

One problem with testing for moisture in soil or for free water is electrolysis of the electrodes. As material is removed from one electrode and deposited on the other (a byproduct of using a dc current), the resistance changes, and

PC’s used to have RS-232 ports to connect things like mice, modems, printers, etc. Then technology moved on to USB. RS-232 had a maximum distance of 50′, and USB is 9′ (USB 3.0) to 16′ (USB 2.0). If you really

The ESP8266 has a current limit of 12ma, so we have to take care when driving relays. First I start with a 817C Optoisolator. The datasheet says says the IR LED drops 1.2v, so I plug 3.3v source voltage, 1.2v

Many ESP8266 12E Boards come with Arduino style pin numbers labeled on the boards, but you use the GPIO pin numbers in your code. If you include the following lines of code in your sketch before setup(), you can use

My Adafruit HUZZAH Feather ESP8266 consumes 0.080 amps (80 ma) in normal operation. With one wire and a single line of code, I can drop that to about 0.010 amps (10 ma), according to my USB power monitor. I connected