s-holst/irtransceiver

A Pmod for emitting and receiving baseband IR signals.

IRTransceiver

A Pmod for emitting and receiving baseband IR signals. It can be used to decode and emulate IR remote controls, IR communication or other IR-based sensors.

This module contains simple analog signal conditioning circuitry to connect a LED and a photodiode to FPGAs or microcontrollers. The interface is a 12-pin Pmod (Spec B) with the following pinout:

• P1: TX, input, active high, controls the IR LED via a simple MOSFET.
• P2: GND
• P3: RX, output, is pulled high if the photodiode receives a stronger-than-average IR light.
• P4: GND
• P5, P11: GND (Pmod power supply pins)
• P6, P12: 3.3V (Pmod power supply pins)
• P7-P10: Not connected

The receiver contains a transimpedance amplifier, a high-pass filter and comparator to produce a clean digital signal. The high-pass rejects ambient light along with signals slower than about 10 kHz, the usable bandwidth is about 100 kHz. The receiver circuit was inspired by IRis.

PYNQ Example Notebook

If you have a PYNQ-enabled FPGA-board, load PYNQ_IR_Communication.ipynb onto it to explore an example of sending and receiving IR signals. This notebook works with the BaseOverlay and is completely self-contained not needing any additional drivers. It expects an IRTransceiver connected to PMODA.