Page 2 of 11
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Sun Sep 27, 2020 5:22 pm
by deviashin
Hello! Thanks a lot for the project!
However, my task is to measure the frequency below or equal to 40 kHz. Please tell me if there is some easier way to do this? Your code does not suit, since I have only one free gpio, and with your approach, at least three are needed
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Mon Sep 28, 2020 10:12 am
by jgustavoam
Hi Deviashin,
As described in the project, you must use three gpios to make the frequency meter.
Use a Port expander for your other needs.
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Mon Feb 08, 2021 9:33 am
by Minatel
Hi Gustavo,
Thank you for sharing your project!
Parabéns!
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Mon Feb 08, 2021 10:44 pm
by jgustavoam
Hi Minatel,
did you test the project?
Thank you,
Gustavo
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Thu Feb 11, 2021 9:05 am
by Minatel
Hi Gustavo,
It's on my list!

Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Tue Mar 02, 2021 11:52 am
by luisr320@gmail.com
Hello Gustavo. Thank you for sharing this project with the community.
I have a question: what would be the shortest time for sampling a frequency? Can it be in the ms range of time?
Greetings form Portugal
Luis
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Tue Mar 02, 2021 9:08 pm
by jgustavoam
Hello Luis,
" What would be the shortest time for sampling a frequency?"
In our project, the sampling time was defined as one second, to give more precision in measuring the frequency.
sample_time = 1000000; ( one million microseconds)
There is nothing to reduce this time, but be aware that you will lose accuracy and that you will have to multiply the measurement value to calculate the frequency..
Best Regards
Gustavo Murta
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Wed Mar 03, 2021 5:30 am
by luisr320@gmail.com
Obrigado Gustavo. I'm develop a wireless fencing scoring system for our club (esgrima) and the wireless part of the system is working very well with ESP32 wonting on ESPNOW, except for the "lack of common ground problem". I need to cancel all the hits to the hand guard and was hopping to do this by detecting a frequency injected on the opponent's metal hand guard. This problem is commonly solved by detecting the capacitance of the hand guard compared with the body but I couldn't find any good solution for this. Would you be willing to help on finding a solution for this problem?
My email is luisr320 @ gmail . com.
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Wed Mar 03, 2021 12:36 pm
by jgustavoam
Bom dia Luis,
If you need help with any project, I suggest you open a new topic in the Lab de Garagem.
https://labdegaragem.com/
https://labdegaragem.com/forum/topic/new
Best regards,
Gustavo Murta
Re: Best Frequency Meter ever made with ESP32 - awesome!
Posted: Sun Jan 09, 2022 6:59 pm
by Armin_PP
Hi Gustavo,
this is an amazing approach to frequency counting, congratulations!
I am not very familiar with interrups, but is it possible to read and count 2-3 frequency signals from different GPIOs at the same time?
Btw. please, allow me a little comment:
Hello Luis,
" What would be the shortest time for sampling a frequency?"
In our project, the sampling time was defined as one second, to give more precision in measuring the frequency.
sample_time = 1000000; ( one million miliseconds)
(..)
I think you mean micro-seconds
