Tag Archives: garage door opener

ATtiny85 operates (fingerprint) garage door opener

A high school sophomore known by the Instructables handle “nodcah” recently designed a DIY fingerprint scanning garage door opener powered by Atmel’s popular ATtiny85 microcontroller (MCU).

Fortunately, the DIY project isn’t limited to just garage doors, allowing Makers and tinkerers to create various types of simple motorized locks by modding the initial Instructables.

Aside from Atmel’s ATtiny85 microcontroller (MCU), key project components include:


Fingerprint scanner and JST connector
  • Serial LCD kit with Atmel’s ATmega328 MCU
PNP transistor
  • Buzzer
  • Speaker wire
  • 3D printed case
  • Copper tape
  • 5V voltage regulator
9V battery and connector
  • SPDT limit switch

“The serial LCD kit sold by Sparkfun comes with an ATmega328 MCU to control the LCD. The ATmega has extra processing power to be used for other tasks besides controlling the LCD. Because of this, we can use it as an Arduino to communicate with the fingerprint scanner, send an ATtiny85 commands, control the LCD and use a buzzer to play tones,” nodcah explained in a detailed Instructables post.

“To prevent the module from running continuously, I’ve added a limit switch to detect when the case is closed. If it’s closed, power will not be supplied to it (saves battery power).”

After gathering the above-mentioned materials, drawing the circuit and assembling the serial LCD kit, nodcah builds the circuit boards, programs the ATmega328 and ATtiny85, configures the fingerprint scanner, writes the sketch and 3D prints a basic case.

“To open the garage door I wired my module to the button that normally opens the garage. Instead of a physical connection being made, the module uses a NPN transistor to ‘press’ the button. The wires should first be measured and cut to size, leaving a little extra wire just to be safe,” nodcah added.

“Then, the hard part: soldering the wires from the button to the FPS module. The wires should next be wrapped with a generous amount of tape. To get the signal from the ATmega outside of the garage to the ATtiny inside the garage, three wires (power, ground and signal) will need to be fed through the wall. On my garage, there was a piece of wood that I just drilled right through.”

Last, but certainly not least, nodcah notes that the module’s built-in enroll feature can be used to open the garage and create personalized messages for each profile.

Interested in learning more? You can check out the project’s official Instructables page here.

Garage door gets an Arduino RFID upgrade

A Maker by the name of Jason955 has designed an RFID-controlled garage door opener using an Atmel-based (ATmega328 MCU) Arduino board.

As HackADay’s Rick Osgood reports, the Arduino acts as the brains of the operation while an off-the-shelf NFC/RFID reader module is tasked with reading the RFID tags.

“To add new keys to the system, [Jason] simply swipes his ‘master’ RFID key. An indicator LED lights up and a piezo speaker beeps, letting you know that the system is ready to read a new key,” Osgood explains.

“Once the new key is read, the address is stored on an EEPROM. From that point forward the new key is permitted to activate the system. Whenever a valid key is swiped, the Arduino triggers a relay which can then be used to control just about anything.”

According to Osgood, the system also offers access to a number of manual controls, including a reset button (erased EEPROM) and a DIP that switch that allows the user to select how long the relay circuit remains open (configurable in increments of 100ms).

As Jason955 points out, the opener pictured above is simply an initial design prototype, with the next iteration likely to be a prototype shield followed by a PCB.

“The top section of components (Arduino and breadboard) will be placed inside the garage and the bottom section of components (LED, buzzer, NFC/RFID reader) will be placed outside (in a project box),” he adds.

Interested in learning more? You can check out the project’s official page here.