It's easy to use the PiCowbell Camera Breakout with CircuitPython and the Adafruit_CircuitPython_OV5640 library. This library allows you to easily write Python code that lets you interface with the OV5640 camera modules.
This example will use the shutter button on the PiCowbell Camera to take a photo with the camera module and save it to a microSD card.
Connect the PiCowbell to a Pico using a PiCowbell Doubler. Insert a microSD card into the microSD card slot on the PiCowbell.
CircuitPython Usage
To use with CircuitPython, you need to first install the OV5640 library, and its dependencies, into the lib folder onto your CIRCUITPY drive. Then you need to update code.py with the example script.
Thankfully, we can do this in one go. In the example below, click the Download Project Bundle button below to download the necessary libraries and the code.py file in a zip file.
Connect your board to your computer via a known good data+power USB cable. The board should show up in your File Explorer/Finder (depending on your operating system) as a flash drive named CIRCUITPY.
Extract the contents of the zip file, and copy the entire lib folder and the code.py file to your CIRCUITPY drive.
Your CIRCUITPY/lib folder should contain the following folder and file:
- adafruit_bus_device/
- adafruit_ov5640.mpy
Example Code
Once everything is saved to the CIRCUITPY drive, connect to the serial console to see the data printed out!
# SPDX-FileCopyrightText: Copyright (c) 2023 Limor Fried for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense
"""
This demo is designed for the Raspberry Pi Pico and Camera PiCowbell
It take an image when the shutter button is pressed and saves it to
the microSD card.
"""
import os
import time
import busio
import board
import digitalio
import adafruit_ov5640
import keypad
import sdcardio
import storage
print("Initializing SD card")
sd_spi = busio.SPI(clock=board.GP18, MOSI=board.GP19, MISO=board.GP16)
sd_cs = board.GP17
sdcard = sdcardio.SDCard(sd_spi, sd_cs)
vfs = storage.VfsFat(sdcard)
storage.mount(vfs, "/sd")
print("construct bus")
i2c = busio.I2C(board.GP5, board.GP4)
print("construct camera")
reset = digitalio.DigitalInOut(board.GP14)
cam = adafruit_ov5640.OV5640(
i2c,
data_pins=(
board.GP6,
board.GP7,
board.GP8,
board.GP9,
board.GP10,
board.GP11,
board.GP12,
board.GP13,
),
clock=board.GP3,
vsync=board.GP0,
href=board.GP2,
mclk=None,
shutdown=None,
reset=reset,
size=adafruit_ov5640.OV5640_SIZE_VGA,
)
print("print chip id")
print(cam.chip_id)
keys = keypad.Keys((board.GP22,), value_when_pressed=False, pull=True)
def exists(filename):
try:
os.stat(filename)
return True
except OSError as _:
return False
_image_counter = 0
def open_next_image():
global _image_counter # pylint: disable=global-statement
while True:
filename = f"/sd/img{_image_counter:04d}.jpg"
_image_counter += 1
if exists(filename):
continue
print("# writing to", filename)
return open(filename, "wb")
cam.colorspace = adafruit_ov5640.OV5640_COLOR_JPEG
cam.quality = 3
b = bytearray(cam.capture_buffer_size)
jpeg = cam.capture(b)
while True:
shutter = keys.events.get()
# event will be None if nothing has happened.
if shutter:
if shutter.pressed:
time.sleep(0.01)
jpeg = cam.capture(b)
print(f"Captured {len(jpeg)} bytes of jpeg data")
print(f" (had allocated {cam.capture_buffer_size} bytes")
print(f"Resolution {cam.width}x{cam.height}")
try:
with open_next_image() as f:
f.write(jpeg)
print("# Wrote image")
except OSError as e:
print(e)
In the code, the microSD card is instantiated over SPI. Then, the camera object is constructed. The shutter button on GP22 is passed as a keypad object. In the loop, if the shutter button is pressed then the camera module takes a picture and it is saved to the microSD card. In the serial monitor, you'll see capture information and confirmation that the image was saved successfully.
Page last edited January 22, 2025
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