Before any APDU, the reader powers the chip, resets it and reads its answer to reset (ATR). EMV Book 1 (application independent ICC to terminal interface requirements) defines what the terminal must do and what it must accept, on top of ISO/IEC 7816-3.
Contact interface and ATR
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Activation, reset, the answer to reset byte by byte, and protocol selection.
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The opening of the article
In the full article
- The contacts
- Activation and reset
- The ATR byte by byte
- Protocol selection
- What goes wrong
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