Transmit speed

[LostOctopus]

Your system information

• Operating system used: Windows
• pyscard version: 2.0.5
• Python version: 3.10.5
• Editor: Pycharm and also in command line

Please describe your issue in as much detail as possible:

The transmit command speed differs even if the script is the same. I run the same script but one time on two, the speed is two times slower. After a quick investigation I observe the behavior described below. Using a profiling tool it seems that it comes from SCardTransmit, I guess this correspond to the PCSC driver or maybe the connection with the interface maybe. The script works each time, but it takes twice longer.

Steps for reproducing this issue:

1. Insert a card in the reader
2. Run the script, check the speed denoted Speed1
3. Re-run the same script, the speed is different denoted Speed2
4. Re-run the same script, the speed go back to Speed1
5. Re-run the same script, the speed switch to Speed2

Remark the speed is always Speed1 just after inserting the card in the reader. If I remove and insert back the card I stay on Speed1 in all cases.

Code

from smartcard.System import readers
from tqdm import tqdm


if __name__ == '__main__':
    # Init reader
    r = readers()
    print(r)
    connection = r[0].createConnection()
    connection.connect()

    # start run using iteration parameter
    nr_commands = 100
    for i in tqdm(range(nr_commands), desc="Progress"):
        my_cmd = "88A000000B11223344556677880A0B0C08"
        data, sw1, sw2 = connection.transmit(list(bytes.fromhex(my_cmd )))

[LudovicRousseau]

I think the "problem" comes from the reader and/or driver.
pyscard has no mechanism to slow down a .transmit().

You can try to write a C program (instead of Python) just to be sure.

You can contact the smart card reader manufacturer.

[LostOctopus]

I changed the reader and effectively this comes from here. Thank you Ludovic. Now I have to find a fast reader.