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Watering woes continue

Nothing is as easy as it seems.

A new attempt at making the watering system operate via a web interface hit a snag. I purchased, and soldered, a new NodeMCU unit. This unit has only 16 pins, as well as the expected ESP8266 chip, but unlike my other two units it also has a 5v pin.
I was excited, hoping that, like an Arduino, the 5v would be available through the signal pins. No such luck. The 5v pin is the only pin with 5v logic; all other pins operate at 3.3v, which is insufficient for the N-channel MOSFET used to control the water pump.

Anyway, a new attempt: using the new NodeMCU unit with a switch relay. The other NodeMCU units couldn't do this as they were entirely 3.3v; the relay requiring 5v to flip the switch, but only needing 3.3v for the signal telling it to do so. Whether my relay works with 12v logic is another matter - I bought it for mains electric control, so it's only ever worked with AC.

Wish me luck.
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  1. Vapor Emergency28 July, 2021 02:29

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