Builds EMV issuer script commands (Script 71/72) that are sent from the issuer to the card via the terminal. Used for PIN changes, card blocking, and data updates on the chip.
Inputs
Command: The type of script command.
Tag: EMV tag to write (for PUT DATA commands).
Tag Value: The value to write to the tag in hexadecimal.
PIN Data: New PIN data (for PIN CHANGE commands).
Encryption Key: Script encryption key in hexadecimal (for encrypted commands).
MAC Key: Script MAC key for command authentication.
ATC: Application Transaction Counter for MAC computation.
Tips
Script 71 is executed before the terminal sends the completion message (pre-Gen AC).
Script 72 is executed after the completion message (post-Gen AC).
The MAC ensures the script was sent by the legitimate issuer.