RFID Unit issues

Patrice

Hi,

I'm using RFID Unid with RFID cards and I experience problems.
I can read UID, if card is on, read and write blocks however I need to go out and put the card back between each command otherwise it doesn't work.
For exemple, if I send 2 consecutive isCardOn(), only the first one returns True, the second one and more return False.

Is there anyone who has experienced the same problem?.

Thanks

m5stack

that is so weird. did you have another card for the test? or all card has same situation?

Patrice

Hi,
Thank you for your reply.
Yes, I tried with 3 other cards and it's the same.
I have done more tests and it is very surprising.

The RFID card is located on the top of the device.
In an infinite loop, I just continuously check isCardOn () and measure the time between each detection.
Without moving the card of the device, I measure 11 detections continuously with 1.2 seconds between each detection and nearly 6 seconds between the 11th and 12th then another 11 measurements with 1.2 seconds .....

If I remove the card and put it on quickly, I can measure times less than 1 second.

Patrice

Hi,

I found a solution.
I have to limit the I2C frequency to 100,000kbps otherwise it won't work properly.
This is strange because a frequency of 400,000 kbps works for all other devices and the MFRC522 should work fine at that frequency.

If anyone has any idea on this limitation, I am very interested.

Thank you