Operating procedure for integrated circuit(s) cards:

This operating procedure applies to every integrated circuit(s) card with contacts.
The dialogue between the interface device and the card is conducted through the consecutive operations:

connection and activation of the contacts by the interface device.

reset of the card.

answer to reset by the card.

subsequent information exchange between the card and the interface device.

desactivation of the contacts by the interface device.

These operations are specified in the following subclauses.

NOTE : An active state on VPP should not only be provided and maintained when requested by the card.

Protocol type T

The four least significant bits of any interface character TDi indicate a protocol type T, specifying rules to be used to process transmission protocols. When TDi is not transmitted, T=0 is used.

T=0 is the asynchronous half duplex character transmission protocol.

T=1 is the asynchronous half duplex block transmission protocol.

T=2 and T=3 are reserved for future full duplex operations.

T=4 is reserved for an enhanced asynchronous half duplex character transmission protocol.

T=5 to T=13 are reserved for future use.

T=14 is reserved for protocols standardized by ISO.

T=15 is reserved for future extension.

NOTE : If only T=0 is indicated, TCK shall not be sent. In all other cases TCK shall be sent.

PTS protocol

Only the interface device is permitted to start a PTS procedure:

The interface device sends a PTS request to the card.

If the card receives a correct PTS request, it answers by sending a PTS confirm, if implemented or the initial waiting time will be exceeded.

After the succesfull exchange of PTS request and PTS confirm, data shall be transmitted from the interface device using the selected protocol type and/or transmission parameters.

If the card receives an erronous PTS request, it will not send a PTS confirm. – If the initial waiting time is exceeded, the interface device should resetor reject the card.

If the interface device receives an erroneous PTS confirm, it should reset or reject the card.

The parameters for the transmission of the PTS request and PTS confirm shall correspond to those used within the Answer to Reset regarding the bit rate and the convention detected by TS and possibly modified by TC1.

Interindustry command for interchange: (ISO 7816-4)

For complete details of commands refer to you chip/interface manufacturers documentation.

This part of ISO/IEC 7816 specifies

the contents of the messages, commands and responses, transmitted by the interface device to the card and conversely,

the structure and content of the historical bytes sent by the card during the answer to reset,

the structure of files and data, as seen at the interface when processing interindustry commands for interchange,

access methods to files and data in the card,

methods for secure messaging,

access methods to the algorithms processed by the card. It does not describe these algorithms.

It does not cover the internal implentation within the card and/or the outside world.
It allows further standardization of additional interindustry commands and security architectures.