> On 17 Feb 2022, at 11:30, Daniel O'Connor <[email protected]> wrote: > > > >> On 17 Feb 2022, at 19:50, Daniel Braniss <[email protected]> wrote: >> >>> If that is the case then the chip/driver are working fine since that >>> requires bidirectional communication etc.. >>> >> >> but that works only if I power up the board while pressing a button, then it >> also appears as /dev/ttyU0, and >> so then I can flash, after reset, the device is gone and there are errors ( >> BTW, the flashed image workes): >> >> Feb 17 09:46:59 pampero kernel: usbd_setup_device_desc: getting device >> descriptor at addr 4 failed, USB_ERR_IOERROR >> Feb 17 09:47:00 pampero kernel: usbd_req_re_enumerate: addr=4, set address >> failed! (USB_ERR_IOERROR, ignored) > > What sort of dev board is it? m5 stamp C3U https://shop.m5stack.com/products/m5stamp-c3u-mate-with-pin-headers?_pos=2&_sid=3df9b5f0d&_ss=r&variant=42341016633601 <https://shop.m5stack.com/products/m5stamp-c3u-mate-with-pin-headers?_pos=2&_sid=3df9b5f0d&_ss=r&variant=42341016633601>
> > Seems very strange the USB UART would behave differently unless it's wired up > in an unusual way IMO. > > -- > Daniel O'Connor > "The nice thing about standards is that there > are so many of them to choose from." > -- Andrew Tanenbaum > >
