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Merge pull request #2677 from caternuson/cp_i2c_scan
Update CircuitPython I2C scanner
2 parents 8cb8889 + f9c17fb commit 9761f26

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  • CircuitPython_Essentials/CircuitPython_I2C_Scan

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CircuitPython_Essentials/CircuitPython_I2C_Scan/code.py

Lines changed: 38 additions & 23 deletions
Original file line numberDiff line numberDiff line change
@@ -2,34 +2,49 @@
22
#
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# SPDX-License-Identifier: MIT
44

5-
"""CircuitPython I2C Device Address Scan"""
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# If you run this and it seems to hang, try manually unlocking
7-
# your I2C bus from the REPL with
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# >>> import board
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# >>> board.I2C().unlock()
5+
# pylint: disable=bare-except, eval-used, unused-import
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7+
"""CircuitPython I2C Device Address Scan"""
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import time
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import board
10+
import busio
1311

14-
# To use default I2C bus (most boards)
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i2c = board.I2C() # uses board.SCL and board.SDA
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# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
12+
# List of potential I2C busses
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ALL_I2C = ("board.I2C()", "board.STEMMA_I2C()", "busio.I2C(board.GP1, board.GP0)")
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# To create I2C bus on specific pins
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# import busio
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# i2c = busio.I2C(board.SCL1, board.SDA1) # QT Py RP2040 STEMMA connector
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# i2c = busio.I2C(board.GP1, board.GP0) # Pi Pico RP2040
15+
# Determine which busses are valid
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found_i2c = []
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for name in ALL_I2C:
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try:
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print("Checking {}...".format(name), end="")
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bus = eval(name)
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bus.unlock()
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found_i2c.append((name, bus))
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print("ADDED.")
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except:
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print("SKIPPED.")
2226

23-
while not i2c.try_lock():
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pass
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try:
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# Scan valid busses
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if len(found_i2c):
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print("-" * 40)
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print("I2C SCAN")
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print("-" * 40)
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while True:
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print(
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"I2C addresses found:",
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[hex(device_address) for device_address in i2c.scan()],
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)
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time.sleep(2)
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for bus_info in found_i2c:
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name = bus_info[0]
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bus = bus_info[1]
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finally: # unlock the i2c bus when ctrl-c'ing out of the loop
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i2c.unlock()
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while not bus.try_lock():
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pass
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print(
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name,
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"addresses found:",
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[hex(device_address) for device_address in bus.scan()],
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)
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bus.unlock()
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time.sleep(2)
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else:
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print("No valid I2C bus found.")

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