diff --git a/examples/pn532_readwrite_mifare.py b/examples/pn532_readwrite_mifare.py
index 3c66a5f..254ef3c 100644
--- a/examples/pn532_readwrite_mifare.py
+++ b/examples/pn532_readwrite_mifare.py
@@ -29,6 +29,7 @@ type RFID tag
 
 import board
 import busio
+# Additional import needed for I2C/SPI
 #from digitalio import DigitalInOut
 #
 # NOTE: pick the import that matches the interface being used