Does the MT20 need to be power cycled before using a configuration card?

Yes, the same process applies like the Schlage reader when using a configuration card.

Disconnect the USB cable from the computer and reconnect after a few seconds.  The MT20 will perform its reset sequence and when it's done, present the configuration card to the MT20 until it responds.  The MT20 will perform its reset sequence again and then it's ready to use.

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