Reset the basic structure and data element of the response Recognition

By definition,The reset response is the value of a series of bytes. These bytes are played by the card as a response to the reset command.

It should be sent to the interface device,InI/OCircuit,Each byte is transmitted in an asynchronous character

Each successful reset operation causesI/OAn initial character onTS, TSFollow the following steps

Sequence followed by maximum32Characters.

 

 

The initial character defines the decoding protocol for all subsequent characters.

The format character declares the first group of interface characters and all historical characters.

Interface characters are specified by bitmap technology declared by formatting characters.

A historical character is specified by a number encoded in a format character.

Verification characters depend on parameters in some interface charactersT.

 

★Initial bytes TS

TSThere are two possible values

The Bytes transmitted during Reverse decoding are equal3f

The transmitted bytes are equal3b

 

 

★Format Byte t0

BytesT0Composed of two parts

BitB8ToB5CompositionY (1):Each equals1Indicates the existence of the successor interface byte.

BitB4ToB1CompositionK: KThe number of historical bytes in the range0To15.

 

 

 

 

 

★Interface bytesTA (I) Tb (I) Tc (I) TD (I)

☆Td (I)

BytesTD (I)Composed of two parts

BitB8ToB5CompositionY (I + 1):Each equals1Indicates the existence of the interface byte.

BB4 to B1.

 

 

☆Ta (1)

 

 

Fi:BitB8ToB5Reference of clock rate conversion factor on

 

 

 

Di: Reference of baud rate correction factor from BB4 to B7

 

 

 

 

☆Tb (1)

B8 is always set to 0, that is, it is not used.

I1:BitB7, B6Reference of the maximum programming current on.

PI1:BitB5ToB1Specifies the value of the programmed voltage.

 

 

These parameters are required by the first-generation smart card, which uses EPROM instead of EEPROM as the data storage, while the latter is the current standard. The high voltage and current required for EEPROM programming are supplied by the terminal through the VPP contact. However, a smart card that never includes an internal charge pump no longer exists. We can ignore this Byte encoding.

 

 

☆Tc (1)

ParametersNIs the extra protection time from the interface device to the card that sends characters from the card to the interface device no additional protection time Default ValueN = 0.

In0To254Before receiving the next character.NIndicates that the previous character of the card must also be followed by the upper-edge delay sent by the card or interface device.

12 etu + (Q *N/f)

FormulaQTake one of the two values:

F/dUsed for computingETU. WhenT = 15Does not exist in the reset response.

FI/diWhenT = 15In the reset response.

N = 255Specifies the minimum delay between two consecutive frontiers during the transmission protocol in two directions.

To.

The minimum latency value is

T = 0Hour12etu

T = 1Hour11etu

 

 

 

★Historical Characters

For a long time, there was no standard to specify historical characters, and the result was that, as the operating system producers differ, they contain a wide variety of data.

Many companies use appropriate bytes to identify the operating system and the associated Rom mask version number. It is usually encoded in ASCII to make it easy to interpret. It is not specified that historical characters exist in the product. You can delete them all. In some cases, such processing can shorten the process and quickly deliver the output.

The data element or history character in the recognition can contain comprehensive information about the smart card and the operating system used. For example, they can be used to store the file selection and implicit selection functions supported by smart cards, as well as information about the logical channel mechanism, they can also be used to store additional information about the serial numbers of publishers, cards and chips, the ROM of the mask, the version number of the chip and the operating system. Data encoding is defined in ISO/IEC7816-4 and-5 standards.

 

★Verification characters

RecognitionThe last byte of is the XOR checksum of the last byte starting from t0 to before the checksum character (TCK. This checksum can be used for verification of the correctness of the recognition transfer except for parity detection.

Reset the basic structure and data element of the response Recognition