5.3.4.3 Request Connection Parameter Update or Update Connection Parameter

Table 5-42. Format
Firmware Version 1.0Firmware Version 1.2 and Later
T,<hex16>,<hex16>,<hex16>,<hex16>[,<hex16>]

UCP,<hex16>,<hex16>,<hex16>,<hex16>[,<hex16>]

Note: All firmware version 1.0 syntax remains valid in version 1.2 and later.
Use command T or UCP to change the following connection parameters:
  • Interval
  • Latency
  • Supervision timeout for current connection
The connection handle received for each connection is appended as the fifth parameter to indicate the target device for multiple links. The parameters of command T or UCP are lost after reboot or power cycle. All parameters are 16-bit values in hex format. Command T or UCP is only effective if an active connection exists when the command is issued.

For more details about the ST command, definitions, ranges and relationships of the connection interval, latency and timeout, refer to Set Central Initial Connection Parameter or Set Initial Connection Parameter. For more details on connection parameters, see Table 5-41.

When command T or UCP with valid parameters is issued by the peripheral device, the minimum interval of timeout is required between two connection parameter update requests. The decision on whether to accept the connection parameter update request is up to the central device. When the RNBD350 module acts as a central device, it accepts all valid connection parameter update requests.

The connection parameters need to adhere to the following rules:
  • Latency <= 30
  • Maximum Interval *1.25 ms*(1+ Latency) <= 4 seconds. (4 seconds = 4000 ms)
  • Maximum Interval *1.25 ms*(1+ Latency) * 5 < Time-out * 10 ms
ItemFirmware Version 1.0 and LaterDescription
Default:Interval: 0020; Latency: 0000; Timeout: 0200 ms
Example:T,0024,0024,0001,00C8Request Connection Parameter to use interval 45 ms, latency 1, timeout 2000 ms
T,0024,0024,0001,00C8,0071Request Connection Parameter to use interval 45 ms, latency 1, timeout 2000 ms and optional assigned connection handle 0071
Response:AOKSuccess
ErrSyntax error or invalid parameter
%ERR_CONNPARM,0071%Status string , connection handle 0071
Note: Apple® iOS® devices have some special requirements for these parameters. The connection parameter update may be rejected if it does not comply with the rules. For more information, refer to the Accessory Design Guidelines on the Apple developer website.
ItemFirmware Version 1.2 and LaterDescription
Default:Interval: 0020; Latency: 0000; Timeout: 0200 ms
Example:UCP,0024,0024,0001,00C8Request Connection Parameter to use interval 45 ms, latency 1, timeout 2000 ms
UCP,0024,0024,0001,00C8,0071Request Connection Parameter to use interval 45 ms, latency 1, timeout 2000 ms and optional assigned connection handle 0071
Response:AOKSuccess
ErrSyntax error or invalid parameter
%ERR_CONNPARM,0071%Status string , connection handle 0071
Note: Apple® iOS® devices have some special requirements for these parameters. The connection parameter update may be rejected if it does not comply with the rules. For more information, refer to the Accessory Design Guidelines on the Apple developer website.