Hi, I know that all Windows IoT is referred back to Windows forums, but just FYI, here is the post I made in their forum because I suspect that this is somehow ACPI related and Qualcomm should be aware of it.
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Hi, the UART device in DragonBoard 410C is broken on this release. Searching by symbolic names UART0, UART1 gives no results. Searching for all SerialDevices we get the ACPI device names:
[UART1] → “\\?\ACPI#QCOM2424#2#{86e0d1e0-8089-11d0-9ce4-08003e301f73}” string
[UART0] → “\\?\ACPI#QCOM2424#1#{86e0d1e0-8089-11d0-9ce4-08003e301f73}” string
However, SerialDevice.FromIdAsync() still returns null with any of those device names. I’m forced to roll back to 2017 release to keep working. That version is not perfect either. StreamReader takes almost 1 second to react after new data arrives, trying different values with .ReadTimeout or .InputStreamOptions.XXX doesn’t make any difference. Something is wrong inside SerialDevice class.