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diff --git a/src/adafruit_blinka/microcontroller/bcm283x/pin.py b/src/adafruit_blinka/microcontroller/bcm283x/pin.py
index 434a90b31c56f48fe63546a54d6b2159ce70d352..5022366a7d4dd1b299b5b17301d5b73beb0d2178 100644 (file)
--- a/src/adafruit_blinka/microcontroller/bcm283x/pin.py
+++ b/src/adafruit_blinka/microcontroller/bcm283x/pin.py
@@ -147,6 +147,9 @@ spiPorts = (
 # ordered as uartId, txId, rxId
 uartPorts = ((1, TXD, RXD),)
 
+# These are the known hardware I2C ports / pins.
+# For software I2C ports created with the i2c-gpio overlay, see:
+#     https://github.com/adafruit/Adafruit_Python_Extended_Bus
 i2cPorts = (
     (1, SCL, SDA),
     (0, D1, D0),  # both pi 1 and pi 2 i2c ports!