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Why can’t I upload to my Arduino Nano?

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.

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Electrolysis Issues with Soil Moisture Sensor

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

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Long Distance Serial with RS-422

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

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Driving Relays with the ESP8266

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

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ESP8266 Deep Sleep Mode

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

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