@ajb2k3
We have tried to connect two RFID reader (https://www.aliexpress.com/item/M5Stack-Newest-Mini-RFID-Unit-RC522-Module-Sensor-for-Arduino-SPI-Writer-Reader-IC-Card-with/32963407976.html?spm=2114.search0104.3.1.3f74370dX6jROf&ws_ab_test=searchweb0_0,searchweb201602_4_10065_10068_319_317_10696_10084_453_454_10083_10618_431_10304_10307_10820_10821_537_10302_536_10059_10884_10887_100031_321_322_10103,searchweb201603_54,ppcSwitch_0&algo_expid=9d7bf1a6-ea97-478a-b8e1-8c3779fd0235-0&algo_pvid=9d7bf1a6-ea97-478a-b8e1-8c3779fd0235&transAbTest=ae803_5) with an IO Expander
(https://www.aliexpress.com/store/product/M5Stack-Official-Extend-Serial-IO-I-O-Unit-Grove-Cable-I2C-Interface-for-Arduino-Blockly-ESP32/3226069_32966582585.html?spm=a2g1y.12024536.productList_5885013.pic_8) with no success.
Should it have to work?
Thanks,

@ajb2k3 Thaks, and can I change the default address?

Hi,
Could you please help me to handle three rfid reader which attached to a hub? I think I should change the default (0x28) I2C address for the other two modules. Or somehow I could initialize the MFRC522 instance with the same address?
Thanks,