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ISO 7816 protocol (SIM card)

I am trying to talk with a device using the ISO 7816 protocol with T = 1. My hardware setup is a microcontroller using USART configured in SIM card mode. I read the relevant documents, but it is not clear what happens after ATR.

  • As far as I understand, the input frequency is used with the initial F = 372, D = 1 in ATR. Therefore, if my frequncy input is 3.571 MHz, the ATR response returns at 9600 baud. This is what I saw in scope and the TTL cable controlling USART. Is it correct?

  • Considering the result of ATR, it shows F = 372, D = 12. Does this mean that the transmission speed for communication with the card is still 9600 baud, or should I send all messages after receiving ATR @, the returned parameters of the transmission speed, for example 115 kbaud? It seems that the PPS runs at 9600 baud, but that doesn't make sense, because F and D return for a different baud rate than the interface on which the card actually runs.

  • Most likely the answer is no, but do PPS and ATR work at a different baud rate than other commands for ISO7816?

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  • Yes, ATR is sent at 9600 baud.

  • 9600 , PPS, . , . F D ATR - , - . ( - , PPS INF, 9600 , reset .) PPS 9600 , .

  • ( PPS).

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