Posted on May 04, 2016 at 17:48
You useHCI_LE_SET_SCAN_RESPONSE_DATA to set the data in the response. I forgot that you also need to put the service UUID's in the packet (probably the most important part!).
In the scan response data, you need the flags AD (0x01), services AD's, and the name AD's (either 0x08 or 0x09; we use 0x09 since we can fit the complete local name in our packet). The flags AD I believe is implicitly added since it's not explicitly defined in our code.
We have only one service. So the basic structure for the data we pass into that method is as follows (Python example from our devkit testing, should be easily translatable to C):
# Device name (we can only fit 10 in our packet)
name_str = ''Example123''
name = list(bytearray(name_str))
len_name = len(name)+1 #The +1 is to account for the AD type byte (0x09)
# Complete list of 128-bit service UUIDs
uuid_list = [0xXX, ..., 0xXX] # (16 bytes, little endian for each 128-bit UUID)
len_list = len(uuid_list)+1 # The +1 is to account for the AD type byte (0x07)
# In order for the services to be found, the scan response data needs to be set.
# + 2 in the Scan_Response_Data_Length accounts for the two AD types (0x07 and 0x09)
response_data = [len_list, 0x07] + uuid_list # 0x07: Complete 128-bit service UUID list
len_resp_data = len(response_data)
HCI_LE_SET_SCAN_RESPONSE_DATA(Scan_Response_Data_Length=len_resp_data+len_name+2,
Scan_Response_Data=response_data + [len_name, 0x09] + name)
Obviously in some cases, it may not optimal to include every service, so just include the one(s) you need. There's an ''incomplete 128-bit UUID list'' for this case. There are AD types for 16-bit UUID's as well.
The complete list of valid AD types is specified here:
https://www.bluetooth.com/specifications/assigned-numbers/generic-access-profile
