Please use an application example from CMSIS pack hci_app sample project which allows placing the RSL10 in direct test mode.
To verify that this application is functioning correctly, use two RSL10 Evaluation and Development boards, or an RSL10 coupled with another third-party peripheral application. Set up the devices to take the roles of device under test (DUT), and lower tester (LT), as instructed in the dtm script
readme file. Use the upper tester (
dtm_script) to send data packets to the DUT. If the packet count received from the LT is consistent with the transfer from the UT (upper tester) to the DUT, the application is functioning correctly. The functionality can be tested and verified further by changing factors such as baud rate, runtime, payload type, and payload length.