"Bottom" IO expander pinout

  • Hello everybody !

    I've ordered M5Stack Basic kit and I'm preparing my project.

    I'm not able to find any schematic / picture that describes the link between MBus to IO of the Bottom module

    Following Schematic:
    MBus have 30 pins with 20 GPIO

    Following Bottom module picture:
    Bottom module come with 46 pins with 30 IO...
    0_1524592014196_Bottom pinout.jpg

    I can figure out connection for 5V, 3V3, GND, RST, BAT but for the other ???

    2 pins are named "DA". What does it mean ?
    "R0"/"T0": RX/TX from UART 1 ?
    "R2"/"T2": RX/TX from UART 2 ?
    "2" means GPIO2 ? So what "G2" means ?

    Anyone can help ? Do you have a document regarding that ?

    Many thanks for your help,

  • Names on the right side correspond to the GPIO numbers on the left and are connected together.

    higher DA mean GPIO25
    lower DA mean GPIO26

    R0/T0 = GPIO3/GPIO1 -> uart0
    R2/T2 = GPIO16/GPIO17 -> uart2

    Similarly, bottom names applies to the gpio numbers at the top.


  • Thanks you so much for your reply !
    So, right now I'm understanding that I will have half IO than expected...

    Thanks again, It helps me a lot
    See you