Hardware Dev Center

Bluetooth Registry Entries

This section describes the class-of-device (CoD) registry subkeys and entries that apply to the Bluetooth driver stack.

"COD Major" and "COD Type" Values

Original equipment manufacturer (OEMs) can use the COD Major and COD Type values to indicate the Class of Device for a Bluetooth-enabled Windows device. After the Bluetooth class installer sets the Class of Device based on these registry values, a remote device can determine whether it is connecting to a portable computer, a desktop computer, a phone, and so on.

The registry path to the COD Major and COD Type values is:


Note that setting these values changes the Bluetooth Class of Device for the system, regardless of which Bluetooth radio may be attached. You can set the COD Major and COD Type to DWORD values as defined for the Class of Device field values in the Bluetooth SIG Assigned Numbers.

The Bluetooth profile driver, BthPort.sys, reads the COD Major and COD Type values to determine how it should respond to a device inquiry. These values affect only the COD_MAJOR_XXX and COD_XXX_MINOR_XXX bits of the Class of Device. The COD_SERVICE_XXX bits are not affected by this registry entry.

If the COD Major and COD Type values are not set or are set to invalid values, the Bluetooth class installer will set these values to COD_MAJOR_COMPUTER and COD_COMPUTER_MINOR_DESKTOP, respectively.

Scanning Parameterization Settings

Profile drivers can specify scanning parameters settings for their device(s) in their profile driver's INF file to tailor to the specific needs of a given device scenario.

You can override the default system scanning parameters by providing one or more of the following scanning parameters listed below into the AddReg directive. More information on how to use this directive can be found on MSDN.

Value NameTypeMin ValueMax Value
HighDutyCycleScanWindowDWORD 0x10001 0x00040x4000. Shall be equal or smaller than the HighDutyCycleScanInterval parameter
HighDutyCycleScanIntervalDWORD 0x10001 0x00040x4000
LowDutyCycleScanWindowDWORD 0x10001 0x00040x4000. Shall be smaller than the LowDutyCycleScanInterval parameter
LowDutyCycleScanIntervalDWORD 0x10001 0x00040x4000
LinkSupervisionTimeoutDWORD 0x10001 0x000A0x0C80
ConnectionLatencyDWORD 0x10001 0x00000x01F4
ConnectionIntervalMinDWORD 0x10001 0x00060x0C80. Shall be smaller or equal to ConnectionIntervalMax
ConnectionIntervalMaxDWORD 0x10001 0x00060x0C80


Note  Changes to scanning parameters make a global impact on the performance of the Bluetooth stack. Making changes to scanning parameters programmatically is not permitted. Using Low Duty Cycle scanning parameters that are too aggressive can not only have a negative impact to the available bandwidth for other Bluetooth Low Energy connections, but also for Bluetooth BR/EDR connections.



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