AndyS19

Nice project, and I'm going to definitely try this. One question though, I usually connect IRLZ44N directly to arduino, with 10K pullup resistor. Why do we need the TC4420 MOSFET driver in this setup? what's the design consideration for using it?thanks,

It's any generic small power transistor , in my case I use 2N3904. I completely forgot to mark that in the drawing. I'll put it in the explanation. thank you,

That's a neat idea, not having to pull out the usb adapter each time. so the additional switch is shorting the reset and GND pins? I don't see why it wouldn't work for other ESP boards, except that you'll have to somehow solder leads that will connect to this adapter. Maybe too troublesome though.. :)thanks for your comment and the neat enhancement.

The step # 2 is the part to get esp-01 into flashing mode. If you're still getting the error means this step is not completed properly. Another possibility might be that you have not installed the driver for the module. After inserting the ESP-01 into your PC's USB, check to see if it's recognized in the device manager. Also make sure to select the correct COM port in the arduino IDE.2. While pressing the button of the tactile switch, insert the adapter into your PC's USB port. Release the button after about 1 sec. You'll be testing your finger's dexterity by doing this exercise.. :)

Here's the new version, which already have a toggle switch. I bought mine sometime ago which has no switchhttps://www.ebay.com/itm/OPEN-SMART-USB-to-ESP8266-ESP-01-Wi-Fi-Adapter-Module-w-CH340G-Driver-Hot/152700861994

Nice, although you technically don't need to add those 10k resistors since they're built in to the adapter board, at least on mine. I tested it with ohmmeter to make sure and it read 10k for both pins.

It would be even cooler to make it real 3D, instead of lighting up the whole row as a single sampling data.. I suggest to add a few msec time delay and variable in arduino to store each of the row separately, and perhaps the front LEDs would be the real time, and then starting to shift to the rear, giving it real 3D look..

From my experience, usually it's not that difficult to figure out the amount of water it needs, with proper tool (syringe with needle). I usually just shine a light into the hole while I'm slowly refilling it, just right above the element/sponges/whatever it's called. You'll see it inside the hole. and then wait for 30mins or so for the water to get absorbed (it it has been dry for a while), and then put more water, same as before, just right above the element.