Xiao expansion board and RFID rc522

Products & Technology XIAO
1

Hi
I have an rc522 rfid module working with the xiao using the expansion board.
Pin connections are:
(Rc522 → xiao)
Sda → 4
Sck → 8
Mosi → 10
Miso → 9
Gnd → gnd
Rst → 3
3v3 → 3v3

This works well. However, as soon as I add code and try to use the built in OLED display and “print” on it, the rc522 stops functioning like there is a hardware conflict. Can someone please tell me how to fix this?

I’m declaring the oled screen instance using “u8x8_ssd1306_128x64_noname_hw_i2c”

Thanks!

2

Figured it out. Switched pin Sda->7 and it’s all working now.

3

Hi, I am struggling getting the XIAO SENSe board working together with RC5322 Rfid reader. Which library do you use for this?