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Dcity_RD200M – Arduino and Particle library for interfacing to the RD200M Radon Sensor
by 
gary
gary
The rd200m library works with Arduino, Particle and other related boards (ESP32, etc.) and it provides many functions to communicate with the RD200M radon sensor module using a serial interface.
RF Low Pass Filter Board 1
by gary
gary
This low pass filter board works well for the HF bands. It also has a notch filter to further reduce the 2nd harmonic.
RF Transmitter/Receiver Relay Board # 1
by gary
gary
This RF relay board is a simple transmitter/receiver relay board that switches the Antenna to either the Receiver or the Transmitter. The relay can be activated in several ways, including by an opto-isolated circuit.
I²C 7 Segment Led Backpack Board (.56 inch Led)
by gary
gary
This project is a backpack board that sits on the back of four digit 7 segment LEDs (.56 inches tall), and it interfaces the LED to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C Keypad Backpack Board
by gary
gary
This project is a backpack board that sits on the back of matrix style keypads (4×4, 4×3, etc.), and it interfaces the keypad to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C OLED Backpack Board for EastRising OLED Display
by gary
gary
This project is a backpack board that sits on the back of [BuyDisplay.com](http://www.buydisplay.com/default/i2c-16×2-oled-serial-character-display-module-screen-yellow-on-black) OLED character displays (16×2), and it interfaces the display to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C OLED Backpack Board for Newhaven OLED Displays
by gary
gary
This project is a backpack board that sits on the back of [Newhaven](http://www.newhavendisplay.com/oled-slim-character-oleds-c-119_825.html) OLED character displays (16×2, 20×2, and 20×4), and it interfaces the display to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C LCD Backpack Board
by gary
gary
This project is a backpack board that sits on the back of many common LCD character displays (16×1, 16×2, 20×2, 20×4, etc.), and it interfaces the display to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C 7 Segment Led Backpack Board (.8 inch Led)
by gary
gary
This project is a backpack board that sits on the back of four digit 7 segment LEDs (.8 inches tall), and it interfaces the LED to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C 7 Segment Led Backpack Board (.36 inch Led)
by gary
gary
This project is a backpack board that sits on the back of four digit 7 segment LEDs (.36 inches tall), and it interfaces the LED to the I²C bus for easy connection to many microcontrollers. A software library is available that works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards.
I²C 7 Segment Led Library for Arduino, Particle, and Raspberry Pi
by gary
gary
The I2c7SegmentLed library works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) microcontroller boards and it provides many functions that make it easy to use the 7 Segment Led display modules (which use the I²C communication protocol).
I²C Keypad Library for Arduino, Particle and Raspberry Pi
by gary
gary
The I2cKeypad library provides easy to use functions for reading a matrix keypad. Library functions such as getKey(), peekKey() and getKeyCount() are included. The I2cKeypad library works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards and it provides many functions to communicate with matrix keypads that use the I²C communication protocol using the MCP23008 interface chip.
I²C OLED and LCD Character Display Software Library for Arduino, Particle and Raspberry Pi
by gary
gary
The I2cCharDisplay library works with [Arduino](http://arduino.cc), [Particle](http://particle.io) (Photon, Electron, and Core) and [Raspberry Pi](https://www.raspberrypi.org) boards and it provides many functions to communicate with OLED and LCD character display modules that use the I²C communication protocol.