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DavidAntliff / esp32-dco

Digitally Controlled Oscillator for the ESP32
MIT License
8 stars 2 forks source link

Tests of precision #1

Open Gustavomurta opened 6 years ago

Gustavomurta commented 6 years ago

Good job David ! Thank you ! I did some tests (dco rmt) , verifying the frequency with my Scope Tektronix TBS1062. In some cases very precise. I think is possible to improve the precision. I will try. 100 KHz => 99,993 Hz good ! 480KHz => 476 Khz 150 KHz => 150,359 Hz 350KHz => 350,780Hz Low frequencies = very precise and stable !

DavidAntliff commented 6 years ago

Thank you for doing these tests. Was this with the RMT or the LED_PWM peripheral? I tend to use the RMT as it has a much wider range of operation than the PWM, but it may be less accurate.

With the RMT peripheral, the choice of APB clock divider is quite important. For some frequencies it may make sense to choose a different divider. I haven't worked out the optimal choice for any frequency yet.

If you can improve things, please consider submitting a PR.

Gustavomurta commented 6 years ago

I did DCO RMT tests. As you reported, DCO LED has a limitation of 10 KHz. I tested this with Arduino IDE. If I make things better , I will tell you.