AN2646 datasheet(40/43 Pages) STMICROELECTRONICS

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Smartcard interface example

AN2646 - Application note

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7.2.3

Enabling/disabling the PIN1 (CHV1) code

At the beginning of the application, the PIN1 (CHV1) status is checked. This can be done by

a GET_RESPONSE command after a successful MasterRoot selection.

In this example, the PIN1 status is checked. If it is enabled, the PIN1 will be disabled to give

access to all files that have a secure access conditions.

To check the PIN1 status, the procedure is the following:

●

Select the MasterRoot directory using a SelectFile APDU command

●

Get the data returned after issuing the MasterRoot SelectFile command by sending a

GETRESPONSE command.

●

Check the bit8 of the 14 received bytes: if bit8 is 0: PIN1 is enabled else the PIN1 is

disabled.

To enable or disable PIN1, the CHV1 code must be sent to the card. The CHV1 code is 8-

byte long.

7.2.4

Verifying the PIN1 (CHV1) code

Some files have a restricted access conditions such as IMSI, CHV1 file, CHV2. The access

conditions of these files must be met for the user to be allowed to execute the restricted

operations (read, update, change CHV1).

To verify the PIN1 (CHV1) condition, the procedure is as follows:

●

Go to the directory which contain the file to be accessed

●

Use the Verify APDU command by presenting the CHV1 code

●

Select the file and execute the selected operation

AN2646 Fiches technique(PDF) 40 Page - STMicroelectronics