Contact array in a card reader

A method of reading a chip card using a card reader, comprising:

• applying, for one or more reader contacts in a plurality of reader contacts, power to the respective contact;
• measuring, for the one or more reader contacts, whether power is being drawn from the respective contact;
• and
• selecting a subset of reader contacts based on whether power is drawn from the one or more reader contacts.

A card reader, comprising:

• a frame having a slot for insertion of a chip card that has a plurality of card contacts, wherein the slot has open sides that allow the chip card to move laterally during the insertion;
• a plurality of reader contacts coupled to the frame and positioned in the slot in a position to be contacted by the card contacts when the chip card is inserted in the slot, and
• circuitry configured to:
• communicate with the chip card through the plurality of card contact, wherein there are more reader contacts than card contacts;
• determine which subset of the reader contacts engages the card contacts and to communicate with the chip card through the subset of reader contacts;
• apply, for one or more reader contacts in the plurality of reader contacts, power to the respective contact;
• measure, for the one or more reader contacts, whether power is being drawn from the respective contact;
• and
• select the subset of reader contacts based on whether power is drawn from the one or more reader contacts.