This module is intelligent car speed measurement module!
The trough type counter photoelectric is used as long as it can be triggered by the non transparent object through the groove type (with the use of the car's code disc in the shop)!
Output 5V TTL level.
Using Schmidt flip flops to shake the pulse, very stable, can be used for measuring the speed of the car, measuring distance and so on!
The four pin is defined as +5 GND OUT1 OUT2, where OUT1 OUT2 is the level output! Direct access to the microcontroller IO port, each road with a LED to indicate its output state