A DIY Sprinkler Controller Using An ESP8266

There is something strangely amusing about the idea of a sprinkler system relying on a cloud. But it was this limitation in some commercial offerings that led [Zack Lalanne] to create his own controller when it was time to upgrade his aging irrigator.

It’s a straightforward enough device, he’s taken an ESP8266 on the ubiquitous NodeMCU board, and added a shift register for some output line expansion to drive a set of relays. The interest here lies with the software, in which he’s used the ESPHome firmware and added his own custom part for the shift register. This change alone should be useful for many other experimenters with the ‘8266 and ESPHome combination.

The ESP8266 end of the device ties in with his instance of the Home Assistant home automation hub software. On this he’s been able to tie in all his various sprinkler outputs he added, and apply whatever automation scripts he chooses. The result is a freshly watered lawn, with not a cloud in the sky (or backend).

The value of this project lies only partly in its use for sprinkler owners, for us it also lies in the clear write-up showing the way for others with similar home automation tasks. It’s not the only way to make an ESP sprinkler controller, you should also see this one from 2017.

Better Debating Through Electronics

Watch any news panel show these days, and you’ll see that things can very quickly become unruly. Guests compete for airtime by shouting over one another and attempting to derail their opponent’s talking points. [cutajar.sacha] had encountered this very problem in the workplace, and set about creating a solution.

The result is the Debatable Deliberator, and it combines the basics of “Talking Stick” practices with behavioural training through humiliation. Two participants each wear a headband, fitted with electronics. The holder of the magic ball may speak for as long as the timer counts down. If their opponent speaks during this time, their headband reprimands them with gentle slapping to the face. If the holder speaks over their assigned time, they are similarly treated to mechanical slapping.

It’s an amusing way to help police a discussion between two parties, and it’s all made possible with a trio of WeMos D1 ESP8266 boards. The headbands act as clients, while the ball acts as a server and keeps track of how many times each speaker has broken the rules.

WiFi projects such as this one have become much easier in the past few years with the wide availability of chips like the ESP8266. Of course, if you need more grunt, you can always upgrade to the ESP32.

Continue reading “Better Debating Through Electronics”

Web Interface Controls Nixie Tube Clock

We love our clocks around here and we love nixie tubes as well. The combination of the two almost seems to be a no-brainer. With the modern twist of an ESP8266, Reddit user [vladco] built a minimalist nixie tube clock.

The build starts with the nixie tubes, Russian In4s, each one mounted on its own small circuit board. Each board is chained together and they’re mounted on a wooden frame. The frame is mounted inside a nice wooden case which was designed in Fusion 360 and milled out of oak at a local hackerspace.

There are no controls on the case. No buttons or knobs. This clock is set via the EPS8266 which gets the time and updates the shift registers that set the numbers on each of the tubes. The clock dims at night so it’s not as bright. [vladco] wrote a web UI to set the time and interact with the  tubes.

The code and files for the case and circuit board are available online. The result is a nice, minimalist clock for your desk. There are plenty of clock builds on the site, several built from nixie tubes, including another nixie tube clock with an ESP8266, and another.

via Reddit

How-To: Mapping Server Hits with ESP8266 and WS2812

It has never been easier to build displays for custom data visualization than it is right now. I just finished one for my office — as a security researcher I wanted a physical map that will show me from where on the planet my server is being attacked. But the same fabrication techniques, hardware, and network resources can be put to work for just about any other purpose. If you’re new to hardware, this is an easy to follow guide. If you’re new to server-side code, maybe you’ll find it equally interesting.

I used an ESP8266 module with a small 128×32 pixel OLED display connected via an SSD1306 controller. The map itself doesn’t have to be very accurate, roughly knowing the country would suffice, as it was more a decorative piece than a functional one. It’s a good excuse to put the 5 meter WS2812B LED strip I had on the shelf to use.

The project itself can be roughly divided into 3 parts:

  1. Physical and hardware build
  2. ESP8266 firmware
  3. Server-side code

It’s a relatively simple build that one can do over a weekend. It mashes together LED strips, ESP8266 wifi, OLED displays, server-side code, python, geoip location, scapy, and so on… you know, fun stuff.

Continue reading “How-To: Mapping Server Hits with ESP8266 and WS2812”

Hack my House: UL Certification and Turning the lights on with an ESP8266

It’s hard to imagine a smart house without smart lighting. Maybe it’s laziness, but the ability to turn a light on or off without walking over to the switch is a must-have, particularly once the lap is occupied by a sleeping infant. It’s tempting to just stuff a relay in the electrical boxes and control them with a Raspberry Pi or micro-controller GPIO. While tempting, get it wrong and you have a real fire hazard. A better option is one of the integrated WiFi switches. Sonoff is probably the most well known brand, producing a whole line of devices based on the ESP8266. These devices are powered from mains power and connect to your network via WiFi. One disadvantage of Sonoff devices is they only work when connected to Sonoff’s cloud.

Light switches locked in to a cloud provider are simply not acceptable. Enter Tasmota, which we’ve covered before. Tasmota is an open source firmware, designed specifically for Sonoff switches, but supporting a wide range of ESP8266 based devices. Tasmota doesn’t connect to any cloud providers unless you tell it to, and can be completely controlled from within a local network.

Certifications, Liability, and More

We’re well acquainted with some of the pitfalls of imported electronics, but one of the lesser known problems is the lack of certification. In the United States, there are several nationally recognized testing laboratories: Underwriters Laboratories (UL) and Intertek (ETL) are the most prominent. Many  imported electronic devices, including Sonoff devices, do not have either of these certifications. The problem with this is liability, should the worst ever happen and an electrical fire break out. The Internet abounds with various opinions on the importance of the certification — a missing certification mark is somewhere between meaningless and a total hazard. The most common claim is that a house fire combined with non-certified equipment installed would result in an insurance company refusing to pay.

Rather than just repeat this surely sage advice from the Internet, I asked my insurance agent about uncertified equipment in the case of a fire. I discovered that insurance agencies avoid giving definite answers about claim payments. The response that came back was “it depends”: homeowner’s insurance covers events that are accidental and sudden. If a homeowner was aware that they were using uncertified equipment, then it could be categorized as “not an accident”. So far, the myth seems plausible. The final answer from the insurance agency: it’s possible that a non UL-certified device could result in denial of payment on a claim, but it depends on the policy and other details– why take the risk? Certification marks make insurance companies happier.

I also talked to my city’s electrical inspector about the issue. He commented that non-certified equipment is a violation of electrical code when it is hard-wired into a house. He echoed the warning that an insurance company could refuse to pay, but added that in the case of injury, there could be even further liability issues. I’ve opted to use certified equipment in my house. You’ll have to make your own decision about what equipment you’re willing to use.

There are some devices on Amazon that claim to have certification, but searching the certification database leads me to believe that not all of those claims are valid. If in doubt, there is a searchable UL database, as well as a searchable Intertek database.
Continue reading “Hack my House: UL Certification and Turning the lights on with an ESP8266”

A Robust ESP8266 RFID Access Control System

By now we’ve seen plenty of projects that use an ESP8266 as a form of rudimentary access control: tap a button on your smartphone, and the door to your apartment unlocks. With the power and flexibility of the ESP, it’s a very easy project to pull off with minimal additional hardware. But what about if you want to get a little more serious, and need to support many users?

Rather than reinvent the wheel, you might want to check out the extremely impressive ESP-RFID project. It’s still based on the ESP8266 we all know and love, but it combines the diminutive WiFi-enabled microcontroller with a nice custom PCB and some exceptionally slick software to create a very professional access control system without breaking the bank. As the name implies, the system is geared towards RFID authentication and supports readers such as the MFRC522, PN532 RFID, or RDM6300. Add in a stack of Mifare Classic 1KB cards, and your hackerspace is well on the way to getting a new door control system.

The official hardware for ESP-RFID can be purchased through Tindie with or without an installed ESP-12F module, but as it’s a fully open source project, you’re also free to build your own version if you’d like. In either event, the board allows you to easily connect the ESP up to your RFID reader of choice, as well as door sensors and of course the door locks themselves.

On the software side of things, ESP-RFID should be able to handle about 1000 unique users and their RFID cards before the relatively limited RAM and storage of the ESP catches up with it. But if you’ve got that many people coming and going in your hackerspace, it might be time to update your systems to begin with. Incidentally, the project makes no guarantees about the security of the ESP-RFID code, and says that the system shouldn’t be used for secure locations. That said, you can run ESP-RFID without an Internet connection to reduce your attack surface, at the cost of losing NTP time synchronization.

If you’re not managing a few hundred users and their RFID cards, one of the more simplistic ESP8266 door locks might be more your speed. We’ve also seen similar tricks pulled off with the Particle Photon, in case you’ve got one of those rattling around the parts bin.

Bringing A Child’s Play Kitchen To Life

Given how many adults will go out of their way to avoid spending any extended amount of time in the kitchen, it’s pretty amazing how much children love playing in their miniature versions. Especially since they tend to be pretty simple: usually they’re little more than different sized boxes made out of MDF to represent the refrigerator, oven, and microwave. Of course, some kids are fortunate enough to have hackers and makers for parents.

[Brian Lough] wanted to get his two year old daughter her own play kitchen, but wasn’t terribly impressed with anything on the market. So he decided to start with the IKEA Duktig and add in his own personal touches to turn the stark white playset into something that would really get his daughter’s imagination going. With the liberal application of RGB LEDs and microcontrollers, her kitchen is sure to be envy of the sandbox.

Being the class act that he is, [Brian] starts his write-up acknowledging the various IKEA Duktig hacks and modifications that served as inspiration for his own build. Most of the prior art out there relates to making the microwave and oven a bit more exciting with the addition of lights and sounds, which ultimately ended up being the way he approached his daughter’s version as well.

For the oven, [Brian] decided to add some big arcade buttons over the door which would change the color of the RGB LEDs inside. He thought this association would be a good way to help his daughter learn her colors, since she’ll be able to see the oven change color when she presses the corresponding button. He also added a knob to control the intensity of the light, meant to be analogous to the temperature control in a real oven.

The modifications to the microwave are a bit more extensive, including a “timer” made out of a TM1637 LED display in a 3D printed panel complete with a buzzer to indicate when the plastic food has been thoroughly illuminated. [Brian] even made it so the LEDs in the NeoPixel ring light up in a spinning pattern to cast some shadows and simulate movement. He notes that the microwave was actually a bit overwhelming to his daughter at first, but after a couple months of getting used to the functions, she enjoys it as much as the oven.

While hacking a play kitchen might be new territory for him, [Brian] is no stranger to building awesome stuff. We’ve previously seen him put together a YouTube subscriber counter in the style of Tetris, and he even managed to create a gorgeous looking display out of shoelaces of all things.