I am working with the Jetracer Pro for my study and I am trying to install a simple speed sensor which has a punched disk rotating through a gate. This gate then measures if there is an obstruction, and the sensor is from the company Joy-IT (Speed sensor LM393 with punched disk).
The supplied manual on their site describes how to connect the sensor to a Raspberry Pi board. This is comparable to the Jetson Nano and has the same GPIO lay-out, so I connected in the instructed way: positive to 3v3, ground to ground and digital output to GPIO 4 or board pin 7. The sensor turns on but no matter if the gate is closed or open, the value on pin 7 stays LOW.
Some tests I have done: The GPIO pin is working and I can communicate with pin 7 (using led test). Then I measured the output voltages on the digital signal, and this went from gate open, 0.2V, to gate closed, 1.1V. Now I understood that the voltage should rise above 1.25V to be switched to HIGH, and so I only receive the output LOW without any switching (using GPIO.RISING and GPIO.FALLING). Now If I remove the connection to pin 7, the sensor switches correctly from 0V to 3.3V.
I can not find any details on why this is not working with the Jetson Nano but it is working with an Raspberry Pi (not tested myself)? And what some of the possible solutions are.
ps. I only now that there is a difference, between the two board types, in current delivered by the GPIO pins, but i don’t see how that is related.
Thanks in advance for the time taken to help