3.1 General Format of HCI Command Packets (Host to BM70/71)

The following figure illustrates the general message format of the HCI Command packet. The HCI Command Packet format and encoding of data is fully documented in the Bluetooth specification, but is briefly listed for completeness. All messages from the host (PC, host microcontroller and so on) to the BM70/71 IC (Device Under Test) follow this format.

Figure 3-1. HCI Command Packet Format

Note: The OPCODE field for the HCI Command is transmitted over the UART LSB first. For example, the OPCODE (0xFC20), byte[1] is 0x20, byte[2] is 0xFC. See HCI Command Packets for the list of HCI commands that are used for the firmware upgrade on the BM70/71.