Reddit reviews HiLetgo 1PC ESP8266 NodeMCU CP2102 ESP-12E Internet WiFi Development Board Open Source Serial Wireless Module Works Great for Arduino IDE/Micropython (Small)

Inspired by /u/commanderkull's post here, I turned an LED-matrix into a performance monitoring tool for my Linux PC. In the gif I am stopping+restarting a Windows VM to show what it looks like when the load changes (of course Windows blue screens, right?)
I wrote a small server to grab the current CPU, memory, and swap usage of my system when the ESP8266 requests it. The ESP8266 then parses the the string and lights the LEDs as necessary.
I have CPU usage displayed in blue LEDs, memory in green, and swap in red. The three colors are added together when displayed (i.e., all the LEDs turn right if each of the above are at 100%)
The code can be found on my GitHub. It's quick and likely dirty, but it gets the job done. The server doesn't cleanly handle the client disconnected+reconnecting right now, but I might add that in the future. As I hinted above, the server only works on Linux right now. Feel free to fork my repo to add Windows support if you like.
This is my first project that I'd consider more or less complete, but it could stand to look a bit nicer. If anyone has any suggestions for that, I'm all ears.

Compnents used:
NodeMCU ESP8266
LED Matrix
Misc. jumper wires

I originally had my garage Controller using an Uno that spoke to an esp8266. I found working with the ESPs AT firmware over serial a royal pain in the ass. I have since switched to just using an esp32 (esp8266 would work just the same) instead of the Uno. The esp boards are much more powerful micros and can still be programmed via Uno. Also I didn't need a logic level convertor between the two. I would seriously consider getting One of these for $9 and cut out the uno completely. What took me days to get working on the Uno/esp combo took an hour with the esp alone.

Hello :-)

What components do you have? Do you have a RC transmitter and RC receiver? Or built-in to some cheap RC car?

Basically he used a multimeter to figure out where each signal "ends up" and an Arduino + optocouplers (to detect the signal without frying the 5v inputs).

If you have a "real" RC receiver, you can read the PWM output (1 2)

If you want to control a car via your computer, consider the ESP8266. It's a micro-controller with built-in wifi. You can get it as a complete board (d1 mini, nodemcu) for under $3 in China or under $10 in the US. Hook up a H-Bridge or motor ESC ($5-$10) and you can skip hacking the existing remote & receiver.

• https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_10?ie=UTF8&qid=1480071357&sr=8-10&keywords=d1+mini
  
  
• https://www.aliexpress.com/item/D1-mini-V2-Mini-NodeMcu-4M-bytes-Lua-WIFI-Internet-of-Things-development-board-based-ESP8266/32681374223.html?spm=2114.30010308.3.8.ufx945&ws_ab_test=searchweb0_0,searchweb201602_2_10065_10068_10000007_10084_10083_10080_10082_10081_10060_10061_10062_10056_10055_10037_10054_10033_10059_10032_10099_10078_10079_10077_10073_10097_10100_10096_10070_423_10052_10050_424_10051,searchweb201603_2&btsid=ce22e2d0-5a85-47cd-8f2f-f96e4fedcb35
  
  Wifi isn't the fastest protocol for such things but it works for some cars.
  
  

You'll need one of these https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_sc_2?ie=UTF8&qid=1495988236&sr=8-2-spell&keywords=ESP+duino

It's a wifi enabled Arduino which you can curl http requests to coinmarketcaps api or any other site to get the ticker value of ETH


I couldn't find the exact display listed here but you should be able to use the digital I/O do drive this https://www.amazon.com/Diymall-Serial-128x64-Display-Arduino/dp/B01HHOETIA/ref=sr_1_1?ie=UTF8&qid=1495988337&sr=8-1&keywords=arduino+mini+display

There are loads of tutorials floating around for arduinos and the display will likely have a public module avail. You can of course use any display.

Wemos and NodeMCU are popular breakout boards for the esp8266. Basically they take the esp8266 and make it easier to work with. You can program them in a variety of ways including the arduino IDE. The downside is there is only 1 analog pin. Since you are intending on using photoresistors you'll have to decide on a workaround since you will need multiple pins. This should be easier to do (and cheaper) than getting wifi up and running on an arduino. In my opinion using an arduino for a wifi project is not worth doing.


I've used the following NodeMCU: https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_2?s=pc&ie=UTF8&qid=1486494246&sr=1-2&keywords=nodemcu


Took me about 10 minutes to get an mqtt connection up and running with the arduino IDE.


I would stay away from starter kits since you have a specific project in mind and just buy a variety pack of resistors, some capacitors, leds, and then whatever you would need for your project. You'll just spend more money on a starter kit and you'll likely need to buy additional parts down the line.

I've built a few of these using this version of the DHT22 - https://www.amazon.com/gp/product/B014SMNBJC/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

It's more expensive because it comes with the resistors and everything already built in, no need for a breadboard.

I've built a few different versions of this, some using the Pi. The Pi is definitely overkill but if you have a B+ laying around then it's no cost to you and you may as well use it. If you want to get something smaller that also works, I am currently running mine off of these NodeMCU ESP8266 boards.

https://www.amazon.com/gp/product/B010O1G1ES/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

The shades are probably over built, after the first set of steppers I tried didn't have enough torque I just said screw out and bought planetary geared steppers, which are a bit pricey.


Nema 17 Geared Stepper Motor Gear Ratio 5:1 3D Printer Extruder Motor DIY CNC Robotics https://www.amazon.com/dp/B00QA5WSDG/ref=cm_sw_r_cp_api_yFTKzbHPVBPDE


SMAKN® TB6600 Upgraded Version 32 Segments 4A 40V 57/86 Stepper Motor Driver https://www.amazon.com/dp/B016ZJS1FA/ref=cm_sw_r_cp_api_uGTKzbJ5XCMGK


HiLetgo New Version NodeMCU LUA WiFi Internet ESP8266 Development https://www.amazon.com/dp/B010O1G1ES/ref=cm_sw_r_cp_api_9GTKzbEZ1TQSP


Outdoor Roller Sun Shade, 6-Feet by 6-Feet, Cabo Sand https://www.amazon.com/dp/B003AU5O2G/ref=cm_sw_r_cp_api_lITKzbW1VKMNA



Here's the post for the pool control stuff:
https://www.reddit.com/r/DIY/comments/6efion/i_built_a_cell_phone_pool_controller_interface/


http://imgur.com/a/qvrCE

I used

$9 NodeMCU (I used it cause its cheap and has easy wifi) https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES/ref=sr_1_3?ie=UTF8&qid=1520488932&sr=8-3&keywords=nodemcu

$1 Light socket https://www.amazon.com/Leviton-8829-CW1-One-Piece-Incandescent-Lampholder/dp/B000HJ97AS/ref=sr_1_1?ie=UTF8&qid=1520488970&sr=8-1&keywords=ceramic+light+socket

A 60 watt light bulb, a usb charger to power the node mcu, some leds for indicators...

You could use one of these guys for $20 and skip all the computer crap: https://www.amazon.com/IMAGE-Display-Auto-tuning-Temperature-Controller/dp/B007JWIDCE/ref=sr_1_4?ie=UTF8&qid=1520489072&sr=8-4&keywords=temperature+pid and then use whatever heat source you want, that wont burn down your home if it gets stuck turned on.

If you want to build a quadcopter, /r/Multicopter and /r/multicopterbuilds are great. They have lots of build guides and advice.

I would just buy one. Focus on one thing at a time. Whatever you do, resist the temptation to get something bigger than a dinner plate. You will underestimate how insanely loud these things are indoors. Smaller quads will also be more resistant to wind and prop backwash. Here's one for $40.

Here's a very good quad for $125 with a very nice camera. The flight controller can be loaded with betaflight, so you can modify the firmware to do whatever you want. Jacking into SPI might be a little hairy.

If you want to build the DWM1001 into the quad, you'll need to be writing C firmware. If you haven't flashed an IC before, then that's kind of jumping right into the deep end. It would be way easier to pull 3.3 V from something and use an ESP8266 or similar. That way you can use Arduino libraries and your life will be way easier.

I've also got a suggestion if you want a longer term goal: SLAM with DSO. Stream video over wifi with websockets to a laptop, do DSO or one of the newer algorithms there, and send instructions back to the quad. From there you can do all sorts of interesting stuff since you're basically generating dense 3d models (point clouds) of real spaces. Vision is huge and full of interesting problems.

I have had very good luck with the HiLetgo boards from Amazon: https://www.amazon.com/dp/B010O1G1ES

Even though a few have released their magic smoke and no longer work.... let's just say that I was conducting "endurance" testing on them... ya, endurance testing... that was it.

Don't think Im dogging you, because I'm not. I think what you did was awesome. But this is a bit over kill. Take a look at something a bit more compact like.

This board is an arduino with built in wifi

Hands down, this is the most useful thing I have created in my time brewing.

I set up a ESP8266 chip with DS18B20 temperature probes. I use the MQTT protocol, which allows for internet connected devices to communicate with each other, to send temperature data to a RPi that is running an Apache server which displays a graph of the temperature over time. I can access this data any time on my local network.

I had done basic Arduino projects up until this point but I had very little trouble setting it up. You can wire up multiple temp sensors in parallel if you have multiple fermentations going on. I use stainless steel thermowells to get the temp inside the vessel. I also use this set up while I am mashing to monitor my temps from a different room.

Here's some of the links I found useful while researching all this.

A basic wiring guide

Basics of setting up MQTT

Displaying the data in a graph

I can provide you with my code if you do decide to go down this route.

Here's what one of my graphs looks like for a mash. The temperature jumps around due to me moving the probe and stirring.

There are definitely a lot of improvements I could make. For one thing, the RPi doesn't save a history of the temperatures it receives, so it will only display data while I have the page up. I have some ideas about how to save this data, just haven't attempted anything yet.

Hey I work in IoT & I'm currently working on some related stuff, but which is totally unrelated to chickens ;)

I have an Rpi around somewhere, but my work is mostly on ESP8266's like the NodeMCU which you can program right in the Arduino IDE.

What are you specifically trying to do? If it's just a webcam... honestly, the off-the-shelf wireless cams are so cheap now that they are certainly a tempting alternative. Also many have motion detection etc.

Not to dissuade you from this project, just sayin ;)

Temp / humidity / light levels are also an option, maybe could get fancy with a methane sensor to determine if the coop needs to be cleaned... scales to weigh the chickens... egg detectors...

If you're willing to fire up the Arduino IDE, you could use just about any ESP8266 product to do this. Here's a NodeMCU board I've been using for projects for less than $10. It's been easier to work with than I expected.

This is way way cheaper than that arduino shield.

​

https://www.amazon.com/gp/product/B010O1G1ES/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

​

You can connect up to 5 of them within their own network, with one as a server, or connect them to a router wifi connection. You just add it as a board in Arduino.

ESP8266 sounds like the best fit. Raspberry Pi needs an extra board to get Analog Input. Arduino needs an extra board for wifi (or an expensive board with wifi built in).
And ESP8266 is easy to use if you have Arduino experience, since the ESP8266 controller uses the Arduino Software. This is a good board to start with.

Basically this project

http://randomnerdtutorials.com/esp8266-dht11dht22-temperature-and-humidity-web-server-with-arduino-ide/

EDIT: I used a higher model sensor so didn't need extra stuff, I could just plug it in

ESP8266

DHT22

and a flat USB cable so I can close the cooler easier

I didn't bother with the Arudino stuff, I have a script that runs and greps the values from the esp webpage and uploads it into mongodb, though I haven't done anything fancy yet with the data, I just check the page to see what it's at.

The esp8266 is perfect for remote sensors. You're going to want the nodeMCU dev board like this one on Amazon.

You can also get them much cheaper ($4 ) on AliExpress if you're willing to wait 3-4 weeks for them to ship from China.

There are two different firmwares that you can flash them with. NodeMCU is allows you to program it using Lua but MicroPython is also available and uses a subset of Python.

what about using a NodeMCU to control a dual relay board?

There are three types of places that you'll commonly work for.

Microsoft shops - IIS, .NET, SQL, Microsoft MVC, ASPX, Ajax

Java shops - Whatever the latest and greatest frameworks and servers are, every place is different. Basically a nightmare to setup if you aren't familiar with it.

Other - Python, Ruby on Rails, Perl, PHP

I've worked for all 3 and would recommend a Microsoft shop. If you are trying to stand up something to show off your skills or practice, I'd say do a full end-to-end implementation of this http://mean.io/ to show off your skills to potential interviewers. It uses, for the most part, the latest and greatest technologies all the way from the DB to the frontend.

The most important part of being a Web dev is having a very good understanding of how it all works from the browser down to the back end. JavaScript runs in browsers and manipulates the html based DOM of the page served by the hosting software. The HTML served is very rarely static, and data is fed and received through the HTTP protocol. Understanding REST-fulness and the stateless nature of the web is key to good development.

If that's not your thing though all you need is a page that hosts a portfolio of your other projects. You could be doing stuff with NodeMCU (Lua, Node.js), Arduinos (C / Assembly), Raspberry Pis (PHP, Python, C) and as long as you post good logs of your projects with source code, interviewers will eat it up seriously. Most of the candidates I interview are not passionate like that, and coming at us with a diverse range of skills and a proven track record of self-motivated projects would get you immediately hired.

You can buy NodeMCUs for like $9 and immediately start coding in Lua or C for a WiFi-enabled microcontroller. The possibilities with this thing are endless and it's the state of the art platform for home based tinkering projects right now.

https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES

http://www.nodemcu.com/index_en.html

The hardware limitations are difficult, but I'm really enjoying the challenge. I've been running mongoose-os on an esp8266 which is great for programming in c or c++. You could pick up a node mcu which is a fantastic low cost development board for the esp8266 and be building your own firmware within a couple days.

Nice! Now do it very low power using an arudino! An ESP8266 can connect to a lot of IOT services and can practically run on a battery for months if you code it right. https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_3?s=electronics&ie=UTF8&qid=1500735601&sr=1-3&keywords=esp8266

Bought from Amazon, like $8.79, Prime.
https://www.amazon.com/gp/aw/d/B010O1G1ES

Just got it today, and never had it loaded with anything at this point.

I also just ordered 2 more from this one.
https://www.amazon.com/gp/aw/d/B01IK9GEQG

Here is the controller https://www.amazon.com/gp/product/B010O1G1ES

It's by hiletgo

i cover this in my jailbreak the ps4 for dummies post above yours here is the usb hd and usb wifi development board i am using:

https://www.amazon.com/gp/product/B00ZTRXFBA/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B010O1G1ES/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

I've used aliexpress or Amazon depending on how quickly I wanted the things.

For a NodeMCU I'd suggest going with the version 2 instead of the version 3 since they fit better on a 400 point breadboard. I generally just search for 'NodeMCU CP2102' which should get you to the version 2.

• amazon link
  
• aliexpress

If you are looking for some more micro controller HW the Node MCU is all the rage for little GPIO projects w/ Python.

https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES

Maybe an ESP32? Has 16 channel 12 bit PWM hardware, integrated bluetooth and WiFi, programmable with the Arduino framework and software. Can get modules of them for around $5-10 https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES/ref=sr_1_10_sspa?ie=UTF8&qid=1526691682&sr=8-10-spons&keywords=wemos+esp32&psc=1

May also want to look into addressable LEDs like WS2812, has RGB or RGBW LEDs and a PWM controller in a single package with a daisy chained serial interface, can have tens or hundereds of LEDs individually controlled with a single pin from the micro. Also available as standalone controller chips to use with separate LEDs, WS2811.

Question about the NodeMCU board... I bought this recently and am having an annoying hard time figuring out what the integer values for the pins should be. These boards have pins labeled D0-D8 but using those as pin values in my code doesn't seem to do anything (I have a simple LED connected and am merely trying to make it blink to start with).

Is this board similar to what you used and did you have any issues figuring out pin mappings? Maybe I'm doing something else wrong...

This is the hardware I used.. The Arduino IDE is here

A nice guide on how to program the ESP8266 chip with the IDE.

Interesting. That’s a good start and the code isn’t too complicated.

I have this ESP8266 board from an old project. Is there an easy way I can have notifications sent to my IOS device when something’s being watered? I want it to be a little smarter than just an Arduino watering based on a sensor input.

https://www.amazon.com/dp/B010O1G1ES/ref=cm_sw_r_cp_api_n36MBb02PSPPW

I'm going to do the same. Are you going to use a specific source code or are you going to write it yourself?

Edit:
Don't really want wait three weeks, so I'm ordering these.
https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/
https://www.amazon.com/dp/B00FDPO9B8/

Haven't really read yet what kind of output the sensors have yet, but I assume it's just the sensitivity, and a boolean for movement. I'll just write a little script that does a HTTP call to my node on movement.

When it comes to frustration, stay away from the cheapest parts unless you can confirm the USB stuff works as expected on your platform. I have wasted too many hours trying to get cheap crap to program from the IDE. Been working with nodemcu lately for
an IoT project and it works well. For less than $10 it's a great way to branch into that stuff while waiting for Adafruit to get the esp32 board back in stock.

https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES

Another point that I don't see mentioned here is if you want to get into it get a decent soldering iron. Once again the cost of a decent tool is worth it compared to the sanity lost fighting with an iron that can't deliver the right temp consistently.

Yeah. You'll probably have to hack the controllers then. You could also check out the ESP8266, they're pretty sleek, and cheap: https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_3?ie=UTF8&qid=1487616893&sr=8-3&keywords=esp8266

The HiLetgo on Amazon seems to be well reviewed and is pretty cheap. How easy would something like this be to use? https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES

Also, to turn on the computer, I have to close a circuit. I could send a signal through one pin, but I'm scared that sending the wrong current could fry my motherboard, so I want to just physically close the circuit. Is there a module that when a pulse is sent to it it will connect two other lines? Like a digital switch? Thanks so much for all your help!

EDIT: just found out the second thing I'm looking for is called a relay :)

Don't even bother. I know this is an "arduino" sub but the [ESP8266] (https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES) (which has a smaller form factor dev board as well) and the ESP32 are cheaper, have more capability, more memory, more GPIO pins, more of everything... Best of all they use the same dev tools, language and libraries that arduino uses. Virtually every single device you can run on an arduino will also run against one of these other microcontrollers.

The ESP32 is the newest microcontroller from the makers of the ESP8266. Way more memory & flash memory, faster dua core CPU, lower power, way more GPIO pins, much better PWM support than the ESP8266, etc. However, because it is newer the library & module support is still not quite as mature as it is for the ESP8266 (at least a year ago when I last used it).

Seriously, if I was in your shoes, I wouldn't even bother with the ardunio if I was going to include wifi. ESP8266 and ESP32 both have them built in.

Again, I know this is an arduino sub but I'm pretty sure it is more of an "cool shit using microcontrollers" sub than strictly an "arduino hardware only" sub. And ESP8266's / ESP32's outclass arduinos in almost every regard.

PS: Most of those wifi shields for arduino actually have an ESP8266 on them in order to get wifi :-)

PPS: The ESP stuff is strictly 3.3v and all the GPIO pins are 3.3v. Arduino is all 5v. If your components all expect 5v and won't work with 3.3v, you'll need to run them all through a logic level converter to step the 3.3v up to 5v and back...

Along with the lights and the ESP8266, you would also need some way to power it and the ESP8266. The LED string I chose is 12v, and the ESP8266 is powered by 5V, so you will need a voltage regulator as well. Also, if you choose the lights I linked they probably wouldn't arrive by the time you need them (they are from a Chinese distributor). What is important is that they are individually addressable WS8211 based. I chose those because they look like a classic christmas light string.

This is as far as I've gotten with the project so far. You also need to set up an environment on your computer to compile the custom firmware that will be flashed to the ESP8266.

I'm afraid that really is no packaged solution for this, so if you don't have a lot of experience with electronics or programming, you may find it an uphill battle.

Good luck!

there are easier solutions but since this is DIY I recently put together a circuit using one of these
https://www.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES/ref=sr_1_1?ie=UTF8&qid=1466965785&sr=8-1&keywords=nodemcu+v3

It's programmed via the arduino IDE and is simple enough with a bit of googling for any programmer to get working. I have it connected to one of these
https://www.amazon.com/SunFounder-Shield-Module-Arduino-Channel/dp/B00E0NTPP4/ref=sr_1_4?ie=UTF8&qid=1466965844&sr=8-4&keywords=arduino+relay

3 wires from the nodemcu to the relay. VCC, ground and one of the datapins. Just make sure you use the 5V pin for VCC as the 3.3V ones didn't work.

Then apply power to the relay and he nodemcu. I used an old 5V cellphone charger that I cut the plug off of and direct wired it to the boards. After that I made a short 6" extension cord and split one of the wires. It goes into the relay. After that it just works.

You will need a way to solder the wires and a breadboard lets you test before doing the final wiring.

I build my own using ESP8266 controllers - they're super cheap ($5), very reliable, built in WiFi, etc. For prototyping or learning get a dev board which has a USB port and pins for a protoboard like this one The company is coming out with a new one called ESP32 ( /r/esp32 ) soon that I will use for most everything. I keep spares so I can just pop in a new one if one fails - so far no failures. We also use Arduino Uno, Arduino Mega and Raspberry Pi.

Sure! http://smile.amazon.com/HiLetgo-Version-NodeMCU-Internet-Development/dp/B010O1G1ES?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00

Don't know if this counts as "good" but I put together a nodemcu and an RF receiver that transmits the codes over MQTT to my raspberry pi. NodeMCU ~$9 https://www.amazon.com/dp/B010O1G1ES/ref=cm_sw_r_cp_apa_3t7.zbNNKST99 and RF receiver ~$7 https://www.amazon.com/dp/B00M2CUALS/ref=cm_sw_r_cp_apa_bx7.zbPBPEM90

Just noticed you said 345mhz... these receivers are made for 433mhz but you might be able to find a similar one for 345mhz?

Let me know if you want any more details.

I don't know what type of communication channel you're using (Z-Wave, Zigbee, RF, etc.) but I use a simple magnetic reed sensor wired to a NodeMCU board. Wifi boards suck down electricity though so my setup has to be mains powered (batteries only last a week or two).

If you want battery powered, look into Z-Wave/Zigbee door sensors; they're more expensive but look nice and can run on battery.

Good to know, thank you. The board will almost solely be controlling lights, maybe looking for a few button presses, so I can probably hit 30 Hz update rate.

I think I'm going to go with one of these ESP8266 NodeMCU boards (e.g. https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B010O1G1ES/ref=cm_cr_arp_d_product_top?ie=UTF8&th=1) as the specs look great and it's got built in wifi too. I'm just wondering why it's so much cheaper than something like the UNO or MEGA. I haven't kept up with recent developments much, are these boards getting outdated and replaced these days? Are there some disadvantages to the ESP8266 I should know of? I'm potentially going to turn this project into a product I can sell so I want something robust.

I don't have any links. I combined multiple sketches to get it to do what I needed. I used a NodeMCU chip (~$8 on amazon) and a cheap 5 pack of PIR sensors

From there I looked up how to connect an esp8266 to wifi, how to publish to mqtt, and how to determine if a pir sensor senses motion.

Combined all that into a working sketch. If I could pull this together, you can too!