Frequency counter input on Mini Maestro

I have a little vauge question about the MiniMaestro and the possibility to use one channel as frequency counter.

For my project, I need to be able to read a speed signal frequency of up to 4000 Hz. As my current script takes about 160 ms to run through the main loop, there is no way I can get even near to reading something like that directly on an input. So my solution is to use a frequency to voltage converter chip. This is neither elegant nor efficient.

At the same time, I know that this would be an easy match for the pic 18F4550 if programmed into the firmware.
So in my mind I am dreaming; what if you have the option of enabling channel 12 as a frequency counter as you now can enable it for PWM! Wow that would open up another new world! :smiley:

Is something like this doable, or would it be too extensive :question:
Is it something that Pololu might consider to do :question:

An optional firmware with frequency counter instead of PWM.


Hello, and thanks for the suggestion.

What is your frequency output coming from, out of curiosity? While this kind of thing would be easy to implement on a bare 4550, the need to generate servo pulses while maintaining USB and UART connections, running scripts, and performing analog conversions pretty much uses up every bit of available processing power, making even measuring a single 4000 Hz signal a challenging task. I think that it would be pretty much impossible to pull off anything that would be useful to you.

By the way, have you considered just using an AVR board such as our Baby Orangutan and programming it yourself? We provide libraries for servo pulse generation and input pulse measurement that would make this straightforward.


I see. All that servo stuff is unneccessary for me anyway.
I ended up with the Maestro because of the 24 I/O channels and USB connectivity.
Also, the Maestro script was pretty easy for a beginner to get into. I managed to put together all neccessary functions in a 4KB script that I got working now.
I am putting together an automatic transmission control unit for off-road use in an ex-mil truck.
The speed signal input is from a Variable Reluctance sensor, that in case would need to be processed through a NCV1124.
The plan is then to put together 20 to 50 units and make software for easy diagnosing and the possibility for each user to set his/her own shift intervals. I got the software ready except the user settings part.

I guess the Baby Orangutan would be more efficient to use not having to run all that servo stuff. But then, 18 channels is not enough. I need minimum 22. Perhaps two Baby Orangutans could be used together to solve that. Then there is the USB. Is it possible to hard-wire the USB AVR programmer and use that the same way as with the Maestro?
B-48 + B-48 + USBprog = 24chMaestro roughly in price.
I somehow managed to fry my second MiniMaestro, exactly same behavior as the first one. Maybe I was too quick to order the third. Maybe Baby Orangutans would be the way to go?