Box, close the contact and download the firmware – Živě.cz

The last few episodes of our series are on electronics programming We are dedicated to building a simple home garage door security system. First, we showed how to use an inexpensive ultrasound or laser rangefinder to find out its current condition. We placed the detector on the roof of the garage and the distance finder measured the distance to the nearest obstacle.

We offered everything on a plate with a famous slice ESP8266Which we can easily program in the Arduino IDE. And since this chip can connect via Wi-Fi at 2.4GHz, we also launched a rudimentary HTTP server, which finally answered us in a web browser on a computer or mobile phone, whether the gateway is currently open or closed.

However, the HTTP server was only available in our home LAN, so in the next part we tried several methods to access the chip from the external internet, for example using the technology. Web socket.

We’ll finish the trilogy with the last two missions. It will be the first Close the electrical contact And the other Remote firmware update – OTA, supported by the ESPxx family’s chipset of course thanks to Wi-Fi, so you can download the new software to a box somewhere in the ceiling of the garage even without a USB cable.

Box, open the gate

Our detector should not only be a passive observer to monitor our current state, but it can also act as a passive observer Operator – Active component that gives the door the command to open or close it via the Internet.

We open most motorized garages by pressing a button on the remote control or a switch on the wall. The switch does nothing but connect the circuit to the pressure, the ECM detects the pulse and either closes or opens the door depending on the current state. But why shut off the circuit with a mechanical button when the ESP8266 Wi-Fi chip can do that directly for us?

Better not to GPIO

Sure, it would have occurred to a green trumpet that it would simply use one of the free digital I / O signals on the chip to connect to the door circuit, i.e. pins that are well known to us. GPIO (GPublic sUrges I am/The) – pins on the prototyping board.

When using GPIO we can access groups Contact directly Various sensors, modules etc.so why wouldn’t that be possible with a garage door? Because prototyping components, such as a small board with a SHT31 digital thermometer, are usually compatible with the operating voltage of our control chip.