<![CDATA[Multiple RFID (RC522) reader via Grove Hub]]>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,

]]>https://community.m5stack.com/topic/510/multiple-rfid-rc522-reader-via-grove-hubRSS for NodeTue, 28 Apr 2026 22:02:10 GMTMon, 14 Jan 2019 16:04:54 GMT60<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Thu, 17 Jan 2019 01:42:09 GMT]]>@ajb2k3
Appreciate you!

]]>https://community.m5stack.com/post/2529https://community.m5stack.com/post/2529Thu, 17 Jan 2019 01:42:09 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Wed, 16 Jan 2019 05:45:11 GMT]]>@watson said in Multiple RFID (RC522) reader via Grove Hub:

@ajb2k3
Thanks guy

We'll make this kind of device

Lol, I can give you loads of product ideas!

]]>https://community.m5stack.com/post/2523https://community.m5stack.com/post/2523Wed, 16 Jan 2019 05:45:11 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Wed, 16 Jan 2019 02:26:44 GMT]]>@ajb2k3
Thanks guy

We'll make this kind of device

]]>https://community.m5stack.com/post/2522https://community.m5stack.com/post/2522Wed, 16 Jan 2019 02:26:44 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 17:52:16 GMT]]>No that is an I/O expander NOT an i2c expander.
you need an i2c expander like this.
link text

]]>https://community.m5stack.com/post/2517https://community.m5stack.com/post/2517Tue, 15 Jan 2019 17:52:16 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 13:34:21 GMT]]>@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,

]]>https://community.m5stack.com/post/2515https://community.m5stack.com/post/2515Tue, 15 Jan 2019 13:34:21 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 06:10:33 GMT]]>@watson said in Multiple RFID (RC522) reader via Grove Hub:

It can not be change the iic address. It has been defined by hardware of RFID module in RFID Unit.

Here's the description about IIC address

0_1547532220523_TIM截图20190115095742.png

ah, so in this case, @falmasi will need to use an i2c expander.
Something like the TCA9548A to use multiple devices on one port.
link text
New product idea for M5Stack?

]]>https://community.m5stack.com/post/2510https://community.m5stack.com/post/2510Tue, 15 Jan 2019 06:10:33 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 06:04:13 GMT]]>It can not be change the iic address. It has been defined by hardware of RFID module in RFID Unit.

Here's the description about IIC address

0_1547532220523_TIM截图20190115095742.png

]]>https://community.m5stack.com/post/2509https://community.m5stack.com/post/2509Tue, 15 Jan 2019 06:04:13 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 05:53:37 GMT]]>@falmasi said in Multiple RFID (RC522) reader via Grove Hub:

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

I don't know as I don't have one.
I was taking a guess based on i2c protocol.

]]>https://community.m5stack.com/post/2508https://community.m5stack.com/post/2508Tue, 15 Jan 2019 05:53:37 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 05:50:21 GMT]]>@ajb2k3 Thaks, and can I change the default address?

]]>https://community.m5stack.com/post/2507https://community.m5stack.com/post/2507Tue, 15 Jan 2019 05:50:21 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Tue, 15 Jan 2019 02:01:09 GMT]]>@falmasi
Hub just for direct connection.

]]>https://community.m5stack.com/post/2502https://community.m5stack.com/post/2502Tue, 15 Jan 2019 02:01:09 GMT<![CDATA[Reply to Multiple RFID (RC522) reader via Grove Hub on Mon, 14 Jan 2019 17:56:55 GMT]]>@falmasi

No, all i2c devices need different address.

]]>https://community.m5stack.com/post/2495https://community.m5stack.com/post/2495Mon, 14 Jan 2019 17:56:55 GMT