I have filed an issue related to HCI UART sample from zephyr running on nrf52832. I compiled the hci_uart sample successfully, but I am not able to use the UART interface through an external USB-UART converter (CP2102 ). I btattach the dev/ttyUSBx and monitor the communication with btmon on the linux host,It indicates that the 52832 chip running hci_uart sample does not respond to the Linux host who sends hci reset command to it.Is anyone met this problem before ？ Any device on debugging and resolving this problem will be highly appreciated,thanks.
The first thing I would do is to verify the UART communication with a digital analyzer. After verifying the the USBtoUART device drives the IO lines according to spec I would run the SDK15\examples\peripheral\uart example in order to verify that the nRF does in fact receive the data correctly. Then I would compare the UART settings from the peripheral\uart example with what is used in the zephyr hci_uart example. Lastly I would set a breakpoint in whatever event handler that is called when UART communication is received, verify that the data received is correct, and if not, read the register of the UART peripheral and compare it to the peripheral/uart example.