Max speed about esp32encoder HOT 1 CLOSED

Runt pulses will be filtered out that last less than 250 ticks of APB_CLK cycles. APB_CLK usually runs at 80mhz a 4x divisor off the system frequency. you need to do some math on your end based on your configuration, but the library's critical value is 250 ticks of the APB_CLK is the minimum pulse time, and assume at least double that speed to be stable. So the minimum pulse is calculates
(250*2)/APB_CLK = minimumUs per pulse

See https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/peripherals/pcnt.html#filtering-pulses for more information on filtering.

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