On the cores3 (module connected through port A), I see no devices found on i2c scan when using esphome. It finds OK on the atom-lite. If using the "Cores3 test" binary from m5stack, I can see the address found on the i2c scan app.

Felix @felmue OMG, this was so easy...many thanks, that was the reason why the unit wasn't reacting for any commands. Have a nice day

I recall the last action before I started to have the issue and I now suspect it was my particular scenario of charging the din base battery that might have damaged one or more of the power distribution mosfets. I shall describe the scenario here as a caution for fellow core s3 owners. firmware installed: uiflow 2.0.1 external device connected: M5Stack GPS/BDS unit connected to port c at the din base. charger used: wall charger with multiple usb c and a ports. one of the usb c port was used. sequence of event: a gps related uiflow program was running and the battery dropped low connected the wall charger to the core s3 with a usb c to c cable to charge the battery inside the din base after some time switched off the core s3 by holding the power button while the charging is still going on core s3 felt very warm to the touch but I did not think too much of it. charging was completed after the red indicator turned off I suspected that in sequence 4 one or more mosfets were overheated and damaged.