HT12E HT12D Encoder Decoder Pair

HT12E and HT12D are normally used to transfer four bit data wirelessly. In this simple circuit, the medium is wire. The HT12E converts the parallel inputs (pins 10, 11,12, and 13) into serial output (pin 17). No need to connect a crystal oscillator to make it work. The data is then received by the HT12D that converts the serial input (pin 14) into parallel outputs (pins 10,11,12, and 13). Four LEDs are connected to the output pins. When a data pin in the HT12E encoder is connected to the positive terminal of the battery, the corresponding LED connected to the HT12D decoder glows. Both IC2 are capable of operating in a wide Voltage range from 2.4V to 12V.