Generic IR Remote Control (21-Button, CR2025)

Connect a standard IR receiver module (like VS1838B) to your Arduino, with its output pin to a digital input pin. Power the receiver with 3.3V or 5V. Install the Arduino-IRremote library via the Library Manager. In your sketch, include the library, define the receiver pin, and use the library's functions to decode the button codes sent by the remote when you press a key. Map each received code to a specific action in your project.

This remote control operates on 3 volts DC, supplied by a single CR2025 coin cell battery. The battery is not included with the remote. Ensure you insert a fresh CR2025 with the correct polarity (positive side facing up towards the contacts) into the battery compartment on the back of the remote for it to function. The low static current design helps maximize the battery's lifespan.

The remote has a nominal line-of-sight transmission distance of up to 8 meters under ideal conditions, though walls or strong ambient light can reduce this. Its infrared LED provides a 60-degree effective emission cone, meaning you do not need to point it directly at the receiver for it to work. For best results, ensure the remote is aimed generally towards the receiver's sensor and that there are no major obstructions blocking the path.

No, this is a standard, fixed-code IR remote. The NEC or similar protocol codes for each button are burned into its internal IC during manufacturing and cannot be changed. To use it, your receiver (like an Arduino with an IR sensor) must be programmed to recognize and act upon these pre-defined codes. You can find the hex code for each button by using a simple sketch with the IRremote library to print received codes to the serial monitor.