After 3 successive orders, the bases have all three a defect of connectivity.
I think the heights of the pins of the contacts are not high enough and do not fit in the header.
View the photo :

It's M5 who has to make the changes?
If not, where can I find the drawing of the changes?
I am a teacher in France who wants to use your products for science education computer and I want to find practical solutions.

Thank you

Hello, I'm having problems with port C. The unitLight sensor does not always give the analog value I think of a false contact with contacts barettes interior (2 * 15). If I screw the two hex screws, the analog input of port C no longer works. If I remove the screws the port C works normally. What can I do for me? See the video Thank you.

I filed a dispute on Aliexpress and the problem is not recognized by M5Stack.

The problem is not the charging of the battery. The battery is charging well
It is a problem of receiving data on the port when the plastic box is screwed.
When the screws are removed all is well.
I think the problem is false contact.

I test the M5Stack products for use with students and I want to have reliable products because I will buy a lot.

What can you do to solve the problem?
Thank you

What is the use of I2C through the USB cable?
Can not upload a program with the usb cable connected to the m5go base?
Being able to upload a program from the charging base would be really cool!
Thank you

@lukasmaximus
The solution you mention is not clean.
It takes a cable groove <--> Dupont.

The jumper / DuPont Female cables can not fit into the Male groove connector because the size of 4 jumpers is larger than the inside size of the groove connector.

@ajb2k3
Thanks again for your answers.
I discover this new product which is fantastic to learn.
You say: "While the light sensor can be connected to port A" but if I connect it as indicated in port A M5 says "ERROR invalid Pin for ADC.
I find normal this answer because the porta = I2C and the light sensor are outputs analog and digital so rather for the port B.
The only solution for me will be to buy the gray base to plug into the M5 Black?
Because I do not want to cut the groove wires to connect them directly to the black M5 core pin connectors.
LF

I think that according to the documentation it is rather the PbHub? Because I / O must be converted to a single I2C. We do not want to have more I2C so it's not PaHub?
But on the presentation video is the M5 Core with a gray module below. The person does not use paHub or pbhub in the video in the link: https://www.youtube.com/watch?v=DgxC_0WGkgk
Thank you for your answer ;-)

Hello,
I bought the core M5 Basic and I want to connect the light sensor with relay module (I want to do as the video presentation). But both have a Grove connection. I think I'm missing a connection module, but which one?
Thanks for your help.