How to send pcsc commands to SAM and not to card on reader

I have acr1281 reader with SAM slot (secure access module). I can communicate with card by pc/sc using python library smartcard. But I want to send commands to the SAM inserted to the reader.

How to 'switch commands channel' for that, is it even possible? smartcard library can send control command to reader (PC_to_RDR_Escape) but in the acr1281 documentation specified only GetFirmvareVersion command.

I even can see that SAM inserted or not - I call SCardStatus() and with SAM inserted get 0x34 code (as I understand this is SCARD_POWERED=0x10 | SCARD_NEGOTIABLE=0x20 | SCARD_PRESENT=0x04), and without SAM it is 0x0c = SCARD_SWALLOWED=0x08 | SCARD_PRESENT=0x04.

But all the commands I send go to MIFARE PICC placed on reader. And I want to send commands to SAM inserted into the reader.

Solution

In Ubuntu Linux with pscs driver installed I have 3 readers in smartcard library:

from smartcard.System import readers
print(readers())

ACS ACR1281 1S Dual Reader 00 00
ACS ACR1281 1S Dual Reader 00 01
ACS ACR1281 1S Dual Reader 00 02

Reader 00 00 is inactive for me, I think it's for contact cards, reader 00 01 is for PICC (MIFARE in my case), reader 00 02 is for SAM slot in ACR,

So I use reader 01 to send card APDU and reader 02 to send commands to SAM and successfully solved my task.

Not sure how to find them automatically but I think that this 00 00 and so on is constants in names and I can select readers for PICC and for SAM by last symbol in their names.

I connect to PICC reader just by smartcard.CardRequest.CardRequest() - waiting for card in proximity. So I have to find only SAM reader and connect to it:

sam_connection = readers()[2].createConnection()
sam_connection.connect(mode=SCARD_SHARE_SHARED,
                        disposition=SCARD_LEAVE_CARD,
                        protocol=SCARD_PROTOCOL_ANY)