Hi all,
I am taking my first steps with the STM32MP257F-EV1, following the "Let's Start" guide on the wiki.
At startup, I get a blinking RED LD1, which stops blinking as soon as I connect the CN15/USB_OTG port of the STM32MP257F-EV1 motherboard using a USB Type-A to Type-C cable and press the Reset button, as indicated in the guide (https://wiki.stmicroelectronics.cn/stm32mpu/wiki/Getting_started/STM32MP2_boards/STM32MP257x-EV1/Let%27s_start/Populate_the_target_and_boot_the_image#Populate_the_SD_card).
The LD1 LED then either stays ON or OFF, but no device is detected under Linux. I have also tried the same procedure on a native Windows machine, but no device appears (even in Device Manager). As a result, no device in DFU mode is detected by CubeProgrammer, either through the GUI or the CLI interface.
Having tried several possible workarounds—such as changing cables, reinstalling drivers and VMs, and reinstalling CubeProgrammer and the supporting software—I analyzed the USB_OTG (DRD) data lines with an oscilloscope. What I discovered is that the USB does not appear to exchange any data at all; instead, it repeats a peculiar "zero pattern" every 250ms. I have attached the oscilloscope printout: D+ in blue, D- in yellow.
This pattern appears only after a reset with the CN15 cable attached and connected to a PC. Otherwise, I get the blinking RED LD1 pattern.
Could someone suggest what I might be doing wrong or if there is a known solution?
Thanks a lot,
Davide
