KeeLoQ compatible Transmitter using ATTiny85
8MHz internal, BOD 2.7v, EEPROM retained, 2 or 4 Buttons. (Burn Bootloader to set the correct fuses)
ATTiny85
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RESET -| / |- V+ Button -| |- Button Button -| |- OOK-Transmitter Data GND -|________|- Button
Buttons = GND when pressed