I am trying to control a guage with a PWM pin on an Arduino UNO. In this case, it is an automotive tachometer. I am getting external input into LabVIEW so I am not interested in using a potentiometer or other device to control it. I find many articles / videos etc. on PWM control but it seems they mostly revolve around a potentiometer for input as opposed to a programmatic signal from digital input.
I attached the VI that I started with. I hooked 12v to the guage and then tied the ground for the 12v to the UNO. I put the signal wire from the tach to pin 3 for PWM control.
As you will see in the VI, I used a dial on the front panel to control the 0-255 pwm output.
I found the guage reacted and then went full scale at a range of about 26 to 36 of the 0-255 available range.
I need to be able to filter/buffer/manage the signal to be less granular and open it up. Ideally, I would like to have the full 0-255 available for control.
After some help from another person on the forums here, it seems I probably need to be sending it a variable frequency signal.
Assuming that is the solution, I am trying to understand how I send that signal. Would anyone have an example VI or maybe a schematic if i need to potentially be lookng at a circuit added into the mix?
Thank you in advance for any thoughts / help you may be able to offer.
Steve P