RE: how to issue rejection to conn parameters update from peripheral device

brave_niuniu — Wed, 22 Oct 2025 08:52:00 GMT

maybe the reason why peripheral device doesn't respond is that the characteristic properties is write_no_rsp

RE: how to issue rejection to conn parameters update from peripheral device

Sigurd — Thu, 30 May 2024 16:23:39 GMT

Ok, good to hear it's working now

RE: how to issue rejection to conn parameters update from peripheral device

tnguyen — Thu, 30 May 2024 16:19:48 GMT

when i changed the write command to write request (w/ response) everything seems to work. Not sure why. I didn't save the log. When I accepted one of the connection parameters update request, it didn't work until i changed the write command to write request (w/ response) and it started working. Not sure why though

RE: how to issue rejection to conn parameters update from peripheral device

Sigurd — Thu, 30 May 2024 08:05:29 GMT

Hi!

Could you save and upload the sniffer trace here?

RE: how to issue rejection to conn parameters update from peripheral device

tnguyen — Wed, 29 May 2024 21:51:57 GMT

I am missing something. The peripheral device doesn't respond to my request after rejecting all the conn param request. Should I have accepted it ?

43 6.573 c9:dc:9c:90:ac:62 LE 1M LE LL 34 149µs CONNECT_IND
44 6.575 Master_0x1be64395 LE 1M ATT 7 1251µs Sent Exchange MTU Request, Client Rx MTU: 247
45 6.575 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
46 6.605 Master_0x1be64395 LE 1M LE LL 9 29632µs Control Opcode: LL_LENGTH_REQ
47 6.605 Slave_0x1be64395 LE 1M ATT 7 151µs Rcvd Exchange MTU Response, Server Rx MTU: 247
48 6.635 Master_0x1be64395 LE 1M ATT 13 29560µs f0ff Sent Find By Type Value Request, GATT Primary Service Declaration, Handles: 0x0001..0xffff
49 6.635 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
50 6.665 Master_0x1be64395 LE 1M LE LL 0 29587µs Empty PDU
51 6.665 Slave_0x1be64395 LE 1M LE LL 2 151µs Control Opcode: LL_UNKNOWN_RSP
52 6.695 Master_0x1be64395 LE 1M LE LL 0 29673µs Empty PDU
53 6.695 Slave_0x1be64395 LE 1M ATT 9 151µs Rcvd Find By Type Value Response
54 6.725 Master_0x1be64395 LE 1M ATT 11 29615µs Sent Read By Type Request, GATT Characteristic Declaration, Handles: 0x0014..0x0019
55 6.725 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
56 6.755 Master_0x1be64395 LE 1M LE LL 0 29603µs Empty PDU
57 6.755 Slave_0x1be64395 LE 1M ATT 20 151µs Rcvd Read By Type Response, Attribute List Length: 2, Unknown, Unknown
58 6.785 Master_0x1be64395 LE 1M ATT 9 29532µs Sent Find Information Request, Handles: 0x0017..0x0017
59 6.785 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
60 6.815 Master_0x1be64395 LE 1M LE LL 0 29620µs Empty PDU
61 6.815 Slave_0x1be64395 LE 1M ATT 10 151µs Rcvd Find Information Response, Handle: 0x0017 (Unknown: Unknown: Client Characteristic Configuration)
62 6.845 Master_0x1be64395 LE 1M ATT 9 29611µs Sent Write Request, Handle: 0x0017 (Unknown: Unknown: Client Characteristic Configuration)
63 6.845 Slave_0x1be64395 LE 1M LE LL 0 150µs Empty PDU
64 6.875 Master_0x1be64395 LE 1M LE LL 0 29619µs Empty PDU
65 6.875 Slave_0x1be64395 LE 1M ATT 5 151µs Rcvd Write Response, Handle: 0x0017 (Unknown: Unknown: Client Characteristic Configuration)
66 6.875 Master_0x1be64395 LE 1M LE LL 0 150µs Empty PDU
67 6.875 Slave_0x1be64395 LE 1M L2CAP 16 151µs Connection Parameter Update Request
68 6.905 Master_0x1be64395 LE 1M L2CAP 10 29060µs Connection Parameter Update Response (Rejected)
69 6.905 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
70 6.935 Master_0x1be64395 LE 1M LE LL 0 29612µs Empty PDU
71 6.935 Slave_0x1be64395 LE 1M L2CAP 16 150µs Connection Parameter Update Request
72 6.965 Master_0x1be64395 LE 1M L2CAP 10 29563µs Connection Parameter Update Response (Rejected)
73 6.965 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
74 6.995 Master_0x1be64395 LE 1M LE LL 0 29609µs Empty PDU
75 6.995 Slave_0x1be64395 LE 1M L2CAP 16 151µs Connection Parameter Update Request
76 7.025 Master_0x1be64395 LE 1M L2CAP 10 29561µs Connection Parameter Update Response (Rejected)
77 7.025 Slave_0x1be64395 LE 1M LE LL 0 151µs Empty PDU
78 7.055 Master_0x1be64395 LE 1M LE LL 0 29610µs Empty PDU
79 7.055 Slave_0x1be64395 LE 1M L2CAP 16 151µs Connection Parameter Update Request
80 7.085 Master_0x1be64395 LE 1M L2CAP 10 29561µs Connection Parameter Update Response (Rejected)
81 7.085 Slave_0x1be64395 LE 1M LE LL 0 150µs Empty PDU

...
130 7.835 Master_0x1be64395 LE 1M ATT 12 29688µs 4154490d0a Sent Write Command, Handle: 0x0019 (Unknown: Unknown)
131 7.865 Master_0x1be64395 LE 1M ATT 12 29827µs 4154490d0a Sent Write Command, Handle: 0x0019 (Unknown: Unknown)

still no response from peripheral device.

RE: how to issue rejection to conn parameters update from peripheral device

tnguyen — Wed, 29 May 2024 21:14:55 GMT

Thanks. That works.

RE: how to issue rejection to conn parameters update from peripheral device

Sigurd — Wed, 29 May 2024 21:09:55 GMT

Hi!

See this Message Sequence Chart:

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.api.v7.2.0/group___b_l_e___g_a_p___c_e_n_t_r_a_l___c_p_u___m_s_c.html?cp=5_7_3_2_2_1_5_2

To reject, call sd_ble_gap_conn_param_update(conn_handle,NULL). If NULL is provided on a central role and in response to a BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST, the peripheral request will be rejected.