similar to the issues that came along with switching to RPi3 (from RPi2) there are again issues with the latest model of RPi (3B+).
Currently I am not able to get my Raspberry Pi booting with resin.io and attached a serial device on the GPIO pins (as they wer working flawlessly with RPi 3).
I modified config.txt and added:
enable_uart=1 and core_freq=250
but Raspberry Pi won’t boot at all (no green light flashing at any time, just permanent red light).
Thank you very much!