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What is it?

A PCB that sits in between your PCB and your NodeMCU(ESP8266), that's why I called it Cheddar, it provides sockets for most of the sensors needed for home automation, in this case, I used Esphome and Home Assistant. In the pictures, the light is not shown as is in reality, in person, it looks more smooth and is not unpleasant to look at, even up close. It will look particularly good in front of a white background.

• I2C, any sensor that supports this it's encouraged to be used as we have a few ports that use it on this board.Some examples

• PIR (presence) AM312, the design admits two of them for a more wide detection range, an example would be a hallway, 1 will work just fine for most use cases.10 PIR presence sensors 1 PIR presence sensor

• Temperature, pressure and humidity, I've tested BME280 using I2C, ATH10 and they all work, I recommend buying just one BME280 for pressure and the rest AHT10 since they're very cheap, less than a dollar, the board also has a Dallas ds18b20 socket, if the temperature is a bit high due to the LEDs heat you can off-set it in Home Assistant or your automation software. Link for BME280 Temp-Hum-Pressure Link for AHT10 Temp-Hum

• Light (lux) tsl2561 tested in I2C socket Link for compatible light sensor

• IR receiver ZIRM1A01-F tested IR receiver + IR blasters

• IR blaster IR leds tested, it can send custom or cloned IR codes to automate most IR receiving appliances IR receiver + IR blasters

• MH-Z19 CO2 sensor tested using the RX/TX pins that are found on a side for easy access and extra sensors CO2 sensor

• A speaker/buzzer port that I found really useful to use as a distributed alarm or notification sound using an ESP8266 for each room. The speaker can be mounted in between the NodeMCU and the PCB or in the front, just remember to use the right polarity. 5.7mm 9mm buzzer.

• 5 W2812B LEDs, one located on the front and 4 in the back for ambient/backlighting, also I use it to display light notifications and home status, for example, they will all display an orange color if I have any window or door opened, this way I can go to sleep without worrying and checking my phone. They will also very smoothly dim and light when any PIR detects movement, a visual way to let you know that the PIR is working its magic. This is all configured on home assistant in my case. WS2812B LEDs in cartridge

Parts needed:

You can use the W2812B without a capacitor as there are only a few of them, the capacitor is to prevent abrupt transitions, I however added the option to solder capacitor near each LED, you could also use the WS2812B variation that has an internal capacitor. Capacitor size: 0805, should be big enough to do it manually but a heated plate makes it easier to solder.

A transistor to drive the IR leds (If you want to use this functionality) any NPN like 2N2222A 2N2222A

Two resistors to drive the IR LEDs and an optional one for the Dallas temperature sensor Link for a kit of resistors

Dallas temperature sensor DS18B20 Dallas sensors pack

Piezo: any 10mm Piezo buzzer. Supplier part: us010t/r-40mpw. 5.7mm 9mm buzzer. 5.7mm 9mm buzzer.

Headers: In case that you want a swappable design, HDR-Female-2.54, cut accordingly. Connector headers

PIR: AM312 10 PIR presence sensors

1 PIR presence sensor

ESP8266: NodeMCU v2, the one with rounded edges. Buy the one with the CP2102 chip. NodeMCU compatible with this PCB

extras: It has two extra pin arrays for other addons and accessibility of every pin of the ESP8266 even SD1 and SD2. The other addon port has two GPIO pins alongside VCC and GND, D3 and D8, this one can mainly be used for a radar sensor like the RCWL-0516. These two pins D3 and D8 are used for the IR receiver and buzzer, have in mind that you shouldn't use one for two sensors. This was done like this because I don't need an IR receiver on my hall but I might need a radar sensor. Radar sensor that works with 3v output to GPIO

Why did I create it?

I created this PCB to avoid soldering, to provide a layer that serves as a motherboard or socket board, also making it easy to display light notifications and miniaturise an ESP8266 sensor array. I was going to create a 3D printed case but for now, I think it looks even better as it is, looks clean and techie, I'll let you know if I create some cases/faceplates.

The PCB LEDs behave like a light strip, the front one is the 1st and the rest follow, so you can split them on esphome, this way you can create different behaviours for them. This is the 8th iteration of this board, an iterative design that I've changed and it evolved to this current more mature design, which should fit most of everyone's needs.

Main advantages over separate sensors or commercial solutions:

• Has multiple i2c socket ports providing scalability and flexibility
• It's good-looking as is, enough to be case-less, a good conversation starter for techies
• Re-usable design
• Swappable by design
• Saves time
• Physical support layer for sensors

What makes it special?

I found this PCB to be goldilocks for rapid prototyping and easily repairing your ESP8266 home automation nodes Why? Because you can solder your sensors and NodeMCU directly into this PCB but also you can do like I do and solder Male and Female headers 2.54mm, that way you can easily fit your NodeMCU into place and the same goes for the sensors, if anything goes wrong you can replace each sensor separately or replace the NodeMCU, no soldering required. But this is your decision.

Pins:

I2C bus -> 3v3, gnd, D1, D2

IR blasters -> D0

PIR sensors -> D6(right), D7(left)

WS2812b LEDs -> D4

EXT pin header -> Vcc, D3, GND, D8

IR receiver -> D3, GND, 3v3

DSB18B20 -> GND, D5, 3v3

Addons header -> VCC, 3v3, GND, TX, RX, SD1, SD2

IMPORTANT: Let me know(send me a message with the desired PCB colour) when you perform a purchase or the PCB colour will be random.

Colours: Black, Blue, White

Home Assistant documentation

ESPhome documentation