`frequencyio` – Support for frequency based protocols

Warning

This module is not available in SAMD21 builds. See the Module Support Matrix - Which Modules Are Available on Which Boards for more info.

All classes change hardware state and should be deinitialized when they are no longer needed if the program continues after use. To do so, either call deinit() or use a context manager. See Lifetime and ContextManagers for more info.

For example:

import time
import frequencyio
import board

frequency = frequencyio.FrequencyIn(board.D11)
frequency.capture_period = 15
time.sleep(0.1)

This example will initialize the the device, set capture_period, and then sleep 0.1 seconds. CircuitPython will automatically turn off FrequencyIn capture when it resets all hardware after program completion. Use deinit() or a with statement to do it yourself.

Available on these boards

ATMegaZero ESP32-S2
Adafruit Camera
Adafruit EdgeBadge
Adafruit Feather ESP32 V2
Adafruit Feather ESP32-C6 4MB Flash No PSRAM
Adafruit Feather ESP32-S2 Reverse TFT
Adafruit Feather ESP32-S2 TFT
Adafruit Feather ESP32-S3 Reverse TFT
Adafruit Feather ESP32-S3 TFT
Adafruit Feather ESP32S2
Adafruit Feather ESP32S3 4MB Flash 2MB PSRAM
Adafruit Feather ESP32S3 No PSRAM
Adafruit Feather HUZZAH32
Adafruit Feather M4 CAN
Adafruit Feather M4 Express
Adafruit FunHouse
Adafruit Grand Central M4 Express
Adafruit HUZZAH32 Breakout
Adafruit Hallowing M4 Express
Adafruit ItsyBitsy ESP32
Adafruit ItsyBitsy M4 Express
Adafruit MagTag
Adafruit Matrix Portal M4
Adafruit MatrixPortal S3
Adafruit Metro ESP32S2
Adafruit Metro ESP32S3
Adafruit Metro M4 Airlift Lite
Adafruit Metro M4 Express
Adafruit Monster M4SK
Adafruit PyGamer
Adafruit PyPortal
Adafruit PyPortal Pynt
Adafruit PyPortal Titano
Adafruit Pybadge
Adafruit QT Py ESP32 PICO
Adafruit QT Py ESP32-S3 4MB Flash 2MB PSRAM
Adafruit QT Py ESP32-S3 no psram
Adafruit QT Py ESP32S2
Adafruit Trellis M4 Express
Adafruit Vindie S2
Adafruit-Qualia-S3-RGB666
Ai Thinker ESP32-CAM
AloriumTech Evo M51
Arduino Nano ESP32
Artisense Reference Design RD00
AutosportLabs-ESP32-CAN-X2
BARDUINO 4.0.2
BDMICRO VINA-D51
BLING!
BPI-Bit-S2
BPI-Leaf-S3
BPI-PicoW-S3
BastWiFi
Bee-Data-Logger
Bee-Motion-S3
Bee-S3
BlizzardS3
CP32-M4
CRCibernetica IdeaBoard
CircuitART Zero S3
CircuitBrains Deluxe
ColumbiaDSL-Sensor-Board-V1
CrumpS2
Cytron Maker Feather AIoT S3
DFRobot FireBeetle 2 ESP32-S3
Deneyap Kart
Deneyap Kart 1A
Deneyap Kart 1A v2
Deneyap Mini
Deneyap Mini v2
DynOSSAT-EDU-OBC
ES3ink
ESP 12k NodeMCU
ESP32 Devkit V1
ESP32-C6-DevKitC-1-N8
ESP32-C6-DevKitM-1
ESP32-H2-DevKitM-1
ESP32-P4-Function-EV
ESP32-S2-DevKitC-1-N4
ESP32-S2-DevKitC-1-N4R2
ESP32-S2-DevKitC-1-N8R2
ESP32-S3-Box-2.5
ESP32-S3-Box-Lite
ESP32-S3-DevKitC-1-N16
ESP32-S3-DevKitC-1-N32R8
ESP32-S3-DevKitC-1-N8
ESP32-S3-DevKitC-1-N8R2
ESP32-S3-DevKitC-1-N8R8
ESP32-S3-DevKitC-1-N8R8-with-HACKTABLET
ESP32-S3-DevKitM-1-N8
ESP32-S3-EYE
ESP32-S3-USB-OTG-N8
Espressif ESP32 DevKitc V4 WROOM-32E
Espressif ESP32 DevKitc V4 WROVER
Espressif ESP32 TTGO T8 v1.7
Espressif ESP32-EYE
Espressif ESP32-LyraT
Espressif-ESP32-S3-LCD-EV-Board
Espressif-ESP32-S3-LCD-EV-Board_v1.5
FeatherS2
FeatherS2 Neo
FeatherS2 PreRelease
FeatherS3
FeatherS3 Neo
Flipper Zero Wi-Fi Dev
Franzininho WIFI w/Wroom
Franzininho WIFI w/Wrover
Freenove ESP32-WROVER-DEV-CAM
Gravitech Cucumber M
Gravitech Cucumber MS
Gravitech Cucumber R
Gravitech Cucumber RS
HMI-DevKit-1.1
Hardkernel Odroid Go
Heltec ESP32-S3-WIFI-LoRa-V3
HexKyS2
IoTs2
Kaluga 1
LILYGO T-DECK
LILYGO T-DISPLAY S3 v1.2
LILYGO T-Display S3 Pro
LILYGO T-Watch-S3
LILYGO TEMBED ESP32S3
LILYGO TTGO T-DISPLAY v1.1
LILYGO TTGO T-DISPLAY v1.1 4M
LILYGO TTGO T8 ESP32-S2
LILYGO TTGO T8 ESP32-S2 w/Display
LOLIN S3 16MB Flash 8MB PSRAM
LOLIN S3 MINI 4MB Flash 2MB PSRAM
LOLIN S3 PRO 16MB Flash 8MB PSRAM
Lilygo T-watch 2020 V3
M5Stack Atom Echo
M5Stack Atom Lite
M5Stack Atom Matrix
M5Stack Atom U
M5Stack AtomS3
M5Stack AtomS3 Lite
M5Stack AtomS3U
M5Stack Cardputer
M5Stack Core Basic
M5Stack Core Fire
M5Stack Core2
M5Stack CoreS3
M5Stack Dial
M5Stack M5Paper
M5Stack Stick C
M5Stack Stick C Plus
M5Stack Timer Camera X
MORPHEANS MorphESP-240
MagiClick S3 N4R2
Maker Go ESP32C6 Supermini
Maker badge by Czech maker
MakerFabs-ESP32-S3-Parallel-TFT-With-Touch-7inch
MicroDev microS2
Mini SAM M4
MixGo CE
NanoS3
Neuron
OMGS3
Oak Dev Tech PixelWing ESP32S2
Oxocard Artwork
Oxocard Connect
Oxocard Galaxy
Oxocard Science
P1AM-200
ProS3
PyCubedv04
PyCubedv04-MRAM
PyCubedv05
PyCubedv05-MRAM
RGBTouch Mini
S2Mini
S2Pico
SAM E54 Xplained Pro
SAM32v26
SQFMI Watchy
Saola 1 w/Wroom
Saola 1 w/Wrover
Seeed Xiao ESP32-C6 4MB Flash 512KB SRAM
Seeed Xiao ESP32-S3 Sense
Seeeduino Wio Terminal
Silicognition LLC M4-Shim
SparkFun MicroMod SAMD51 Processor
SparkFun Thing Plus - SAMD51
Sprite_v2b
Sunton-ESP32-8048S050
Sunton-ESP32-8048S070
TG-Boards' Datalore IP M4
TTGO T8 ESP32-S2-WROOM
Targett Module Clip w/Wroom
Targett Module Clip w/Wrover
The Open Book Feather
ThingPulse Pendrive S3
TinyC6
TinyPICO
TinyPICO Nano
TinyS2
TinyS3
TinyWATCH S3
UARTLogger II
VCC-GND YD-ESP32-S3 (N16R8)
VCC-GND YD-ESP32-S3 (N8R8)
VIDI X V1.1
Waveshare ESP32-S2-Pico
Waveshare ESP32-S2-Pico-LCD
Waveshare ESP32-S3-GEEK
Waveshare ESP32-S3-Pico
Waveshare ESP32-S3-Tiny
Waveshare ESP32-S3-Zero
Waveshare ESP32S3 LCD 1.28
WeAct ESP32-C6 (4MB)
WeAct ESP32-C6 (8MB)
WeMos LOLIN32 Lite
Winterbloom Sol
nanoESP32-S2 w/Wrover
nanoESP32-S2 w/Wroom
senseBox MCU-S2 ESP32S2
sunton_esp32_2432S028
sunton_esp32_2432S032C

class frequencyio.FrequencyIn(pin: microcontroller.Pin, capture_period: int = 10)

Read a frequency signal

FrequencyIn is used to measure the frequency, in hertz, of a digital signal on an incoming pin. Accuracy has shown to be within 10%, if not better. It is recommended to utilize an average of multiple samples to smooth out readings.

Frequencies below 1KHz are not currently detectable.

FrequencyIn will not determine pulse width (use PulseIn).

Create a FrequencyIn object associated with the given pin.

Parameters:

pin (Pin) – Pin to read frequency from.
capture_period (int) – Keyword argument to set the measurement period, in milliseconds. Default is 10ms; range is 1ms - 500ms.

Read the incoming frequency from a pin:

import frequencyio
import board

frequency = frequencyio.FrequencyIn(board.D11)

# Loop while printing the detected frequency
while True:
    print(frequency.value)

    # Optional clear() will reset the value
    # to zero. Without this, if the incoming
    # signal stops, the last reading will remain
    # as the value.
    frequency.clear()

deinit() → None: Deinitialises the FrequencyIn and releases any hardware resources for reuse.

__enter__() → FrequencyIn: No-op used by Context Managers.

__exit__() → None: Automatically deinitializes the hardware when exiting a context. See Lifetime and ContextManagers for more info.

pause() → None: Pause frequency capture.

resume() → None: Resumes frequency capture.

clear() → None: Clears the last detected frequency capture value.

capture_period: int: The capture measurement period. Lower incoming frequencies will be measured more accurately with longer capture periods. Higher frequencies are more accurate with shorter capture periods.

Note

When setting a new capture_period, all previous capture information is cleared with a call to clear().

__get__(index: int) → int: Returns the value of the last frequency captured.

frequencyio – Support for frequency based protocols

`frequencyio` – Support for frequency based protocols