Hey @Powersoft sorry for the late reply you can find the arduino code here https://github.com/m5stack/M5Stack/tree/master/examples/Unit/NEOFLASH

@Sebastian glad rick could help, I thought he might. Great work, if you get chance it would be nice to see a full guide on our hackster page hackster.io/m5stack

Then which one would work for me?

Do you use RFID unit or base

@koiexp I'm running it at 12v without any issues. Contact details - https://m5stack.com/pages/contact-us

@dda That would make sense now that I think about it as Wire is i2c0 which is routed to the grove port. Thank you for taking the time to work it out and solve it. BTW can you edit you title and put [Solved] at the beginning of the title to show that the issue is solved.

Thanks for your replies, i tried the proposed arduino example and unfortunately got the same results - no response from the bmm. I will contact the shop have a nice day Chris

Hi cncninja, currently the USB module hasn't been added as there are no micropython drivers for it. You can use the USB module with Arduino, there are a few examples and code on our docs page https://docs.m5stack.com/#/en/module/usb let me know if you get stuck

I share m5 support answer on the topic "UART0 is a specifically assigned for log print, it is encapsulated by ESP32 at lower layer. It will print the system log automatically and seems like we users are not permitted to shut it down, so we don’t recommend users to use UART0 as a normal UART series port, it will interrupt you communication. That why we connect it with CP2104." to me it's clear the usage of UART0 ..less cleare why this two GPIO are routed to the M5bus since can't be used I will use UART2 for my custom project with this assignment GPIO34=RX GPIO17=TX Davide

And the PCB files for ordering the board from JLCPCB. PCB layout of the MBUS referance.

@ajb2k3 Really thanks for your reply