I think the issue is due to OpenOCD being compiled without any HID API library. Do you have either "hidapi-hidraw" or "hidapi-libusb" installed?
When there is no HID library, the OpenOCD command "cmsis-dap backend hid" returns the error message "invalid backend argument to cmsis-dap backend <backend>" which, by the way, is not the ideal outcome! At the end of the configure, the build system dumps the table "OpenOCD configuration summary" but it does not report anything explicitly about HID! Anyway, the line CMSIS-DAP v2 Compliant Debugger yes (auto) is for the "usb_bulk" backend, while the line CMSIS-DAP Compliant Debugger yes (auto) is for the "hid" backend. Check that this last line reports "yes" in your build. I think we have some improvement to code here: - report USB and HID in the configuration summary instead of v2 vs nothing - eventually extend the summary to report the libraries found - modify the command "cmsis-dap backend" to always recognize the options "usb_bulk" and "hid" and report if the option is not available. Antonio
