Adding 128 bit service uuid in advertising payload

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Last post
Thu, 2020-10-01 14:51
#1
prasanna
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Adding 128 bit service uuid in advertising payload

Hi,

I am trying to include the 128 bit service UUID in the advertising payload. I have tried to include in the adv_data as I did for other advertising elements like local. Please find the code attached below. If I try to run this, I cannot detect the peripheral at all. Firstly, I wanted to know is this the correct way to include the 128 bit UUID in the advertising payload or do I need to make use of functions defined in the ble_UUID.h. If so, could you explain how to do this (with an example if possible).

code

static const uint8_t adv_data[] = {
0 x04 GAP_DATA_TYPE_SHORT_LOCAL_NAME
'P', 'A', 'C',
0x03, GAP_DATA_TYPE_MANUFACTURER_SPEC, 0, 210,
0x02, GAP_DATA_TYPE_TX_POWER_LEVEL, 3,
0x11, GAP_DATA_TYPE_UUID128_LIST, 38, 174, 43, 4, 28, 220, 124, 186, 74, 74, 2,
189, 7, 77, 231, 35
};

Thanks in advance.

Device:
DA1469x
Fri, 2020-10-02 13:38
PM_Dialog
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加入:2018-02-08 11:03
Hi prasanna

Hi prasanna

Please read the comments above the ble_gap_adv_data_set() :

"...The maximum Advertising Data length for undirected connectable advertising is BLE_ADV_DATA_LEN_MAX bytes (31 minus 3 that are reserved to set the Advertising Data type flags - which shall not be set in Advertising Data using this function)...*

In your case, the advertising data exceed the max value, so you should use the scan response data as well.

static const uint8_t adv_data[] = { 0x04, GAP_DATA_TYPE_LOCAL_NAME , 'P','A', 'C', 0x03, GAP_DATA_TYPE_MANUFACTURER_SPEC, 0x00, 0x01, 0x02, GAP_DATA_TYPE_TX_POWER_LEVEL, 0x03, }; static const uint8_t scan_resp[] = { 0x11, GAP_DATA_TYPE_UUID128_LIST, 0x11, 0x22, 0x33, 0x44, 0x00, 0x08, 0x54, 0x8F, 0x53, 0x41, 0x47, 0x45, 0x60, 0xC6, 0x56, 0xAA, }; /* Set advertising data */ ble_gap_adv_data_set(sizeof(adv_data), adv_data, sizeof(scan_resp), scan_resp);

You could use different UUID and manufacturer data according to your requirements.

Thanks, PM_Dialog

Accepted answer
Fri, 2020-10-02 16:28
prasanna
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Dear PM_Dialog,

Dear PM_Dialog,

According to the maximum data you said (31 bytes -3), we are remained with 28 bytes. In my case I am using 4Bytes for local name, 3 for manufacturer data, 2 for tx power and 17 for UUID which results in 26 bytes lower than the allowed maximum bytes. I don't understand how am I exceeding the maximum payload.

注册ards,

Prasanna

Sun, 2020-10-04 10:34
(Reply to #3)
prasanna
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Dear PM_Dialog,

Dear PM_Dialog,

I understood what was wrong. Some confusion in counting the number of bytes of payload. Now its clear. Thanks once again :)

注册ards, Prasanna

Mon, 2020-10-05 14:11
PM_Dialog
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Hi prasanna,

Hi prasanna,

Thanks for accepting my answer and glad that you make it working. If you have any other follow-up question, please raise a new forum thread.

Thanks, PM_Dialog