A bodged presentation clicker based on two parts. The transmitter is an Attiny85 and the Receiver is an STM32F103.
+-------------------------------------------------------+
| |
| IR LED |
| BUT1 t85 |
| +-------+ XXXX |
| +--+ | +-----+XXXX |
| +--------+ +---------+ | XXXX |
| | | | |
| +--------+ +---------+ | |
| | +--+ +-------+ |
| +---+ + |
| +-+ BUT2 | |
| + | |
| <-----------+ |
+-------------------------------------------------------+
|
|
|
+-----------+
|
+---------------+---------------------------------------------+
| |
| TL 1838 |
| |
| XXXXX |
| XXXXX+ +------------------------------+ |
| XXXXX| | | USB HID |
| | | STM32F103 | AS A |
| +------+ +---------> |
| | | KEYBOARD |
| +------------------------------+ |
| |
| |
| |
+-------------------------------------------------------------+