A1: The cable we sold with NFC shield is 12cm. If you want a longer one yourself, please no more than 15cm with a IPX/U.FL connector.
Q2: Why I always got error "Didn\'t find PN53x board" while using NFC shield with M1 RFID card (13.56Mhz)?
A2: Please use the sketch "mifareclassic_formatndef" under "PN532" library to format the card, then try with "ReadTag" again.
Q3: Can two or more antennae be added to NFC Shield V2.0 (SKU: 113030001)?
A3: NFC shield v2 is based on PN532 chip. Please note that the design only supports one antenna.
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