Why doesn't my GPIO pin stay high below 200 Hz in my frequency counter code?
I'm using a frequency counter code from Deep Blue Embedded to monitor RPM via a tachometer and trigger a relay when the frequency drops below 200 Hz. However, the output on pin PB14 doesn't stay high at low frequencies (tested between 100 Hz and 500 Hz). The signal on the oscilloscope fluctuates instead of staying steady. Here's the relevant portion of the code I'm working with:
Even when the frequency drops below 200 Hz, the pin doesn’t stay high as expected. Could the leftover UART code (without a connected hardware) be causing this? Also, I tried using PA0, but it didn’t work either. How can I safely remove the UART code without breaking the program?
Even when the frequency drops below 200 Hz, the pin doesn’t stay high as expected. Could the leftover UART code (without a connected hardware) be causing this? Also, I tried using PA0, but it didn’t work either. How can I safely remove the UART code without breaking the program?
Solution
The frequency counter might not be reading consistently at lower frequencies.add a small debounce delay or hysteresis to stabilize the pin state. The UART code likely isn't affecting this, but if unused, you can comment it out or disable UART in the initialization code to avoid resource conflicts. For PA0 not working, ensure it's not reserved for other functions, like input capture.
