RTL8773E Motherboard User Guide
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3.2.2 BLE Direct Test Mode
- Test RTL8773E Motherboard for BLE Test Item through HCI UART Interface
This part describes the direct test mode (DTM) mechanisms for testing BLE items and
explains how the direct test mode connection is established.
The DTM mode requires a direct connection to the Bluetooth measurement instrument.
RTL8773E Motherboard use HCI UART interface to connect to the Bluetooth
measurement instrument as Figure 3-5.
Bluetooth measurement
equipment
RX
TX
RF Cable
Figure 3-5 DTM mode RF test hardware connection
If Bluetooth measurement instrument interface is RS232, you need a level shift board,
such as MAX232 in Figure3-6.
Bluetooth measurement
equipment
RX
TX
RF Cable
Level Shift
Figure 3-6 Level shift for RS232
If Bluetooth measurement instrument interface supports USB interface, a USB to
UART converter may be needed, such as FTDI USB converter board in Figure 3-7.