SC2262 / SC2272 Emulation in Software Testing

A study for datalogging Harbor Freight PIR sensors

Once upon a time I had a need to decode a RF remote control for a project. The remote control used an encoding chip SC2262. A second source for the part is PT2262. The typical receiver for these signals use variations of a decoder chip SC2272 or PT2272.

A recent project needed to log activations from multiple PIR sensors. The particular PIR sensors are sold by Harbor Freight. The sensor uses the SC2262 encoder. Each PIR comes with a matching receiver that puts out an annoying double beep for every trigger of the PIR sensor. The receiver uses a decoder chip with proprietary markings. It may or may not be SC/PT2272 variant. It doesn't matter since Harbor Freight channel numbers are based on the address mode instead of using the data nibble. The typical SC/PT2272 chips don't provide the address as an output. They look for a specific address and signals you when that address is detected. This arrangement is not suitable for tracking multiple sensors.

What was needed is a receiver that can receive and decode broadcasts from multiple PIR sensors.

This Arduino code receives the raw data stream, isolates all 12 bits of address and data of the SC2262 protocol, making it available to the program for further processing. It took a little effort to figure it out, but not that hard given the spec sheet.

Part of the project needed some kind of relaying device to extend the range and/or change the data for some sensor locations. So the SC2262 encoding code was also ported to Arduino code.

The code presented here is definitely a hack. It does not show the whole project. Just the bits for testing the encoding and decoding of the protocol. It does not use any library features, but is easy to follow as to what is going on, I hope. It does work, but could use some clean up.

PT2272_SIM.ino PT2272_SIM.ino

PT2262_SIM.ino PT2262_SIM.ino

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