BTM services

btm

This is "nn::btm::IBtm".

Support for "nn::btm::*" was added to sdknso with 6.x.

This has max_sessions 6. IPC is handled by 2 threads shared with all services.

These btm services with BLE only allow connecting to devices which have a #GattService with a certain custom UUID present.

The output bool from all of these btm* service get-event cmds indicates whether the Event was successfully returned, user-processes will Abort when this is 0.

Cmd	Name
0	#GetState
1	#GetHostDeviceProperty
2	#AcquireDeviceConditionEvent
3	#GetDeviceCondition
4	#SetBurstMode
5	#SetSlotMode
6	[1.0.0-8.1.1] #SetBluetoothMode
7	#SetWlanMode
8	#AcquireDeviceInfoEvent
9	#GetDeviceInfo
10	#AddDeviceInfo
11	#RemoveDeviceInfo
12	#IncreaseDeviceInfoOrder
13	#LlrNotify
14	#EnableRadio
15	#DisableRadio
16	#HidDisconnect
17	#HidSetRetransmissionMode
18	[2.0.0+] #AcquireAwakeReqEvent
19	[4.0.0+] #AcquireLlrStateEvent
20	[4.0.0+] #IsLlrStarted
21	[4.0.0+] #EnableSlotSaving
22	[5.0.0+] #ProtectDeviceInfo
23	[5.0.0+] #AcquireBleScanEvent
24	[5.1.0+] #GetBleScanParameterGeneral
25	[5.1.0+] #GetBleScanParameterSmartDevice
26	[5.1.0+] #StartBleScanForGeneral
27	[5.1.0+] #StopBleScanForGeneral
28	[5.1.0+] #GetBleScanResultsForGeneral
29	[5.1.0+] #StartBleScanForPairedDevice
30	[5.1.0+] #StopBleScanForPairedDevice
31	[5.1.0+] #StartBleScanForSmartDevice
32	[5.1.0+] #StopBleScanForSmartDevice
33	[5.1.0+] #GetBleScanResultsForSmartDevice
34	[5.1.0+] #AcquireBleConnectionEvent
35 ([5.0.0-5.0.2] 24)	[5.0.0+] #BleConnect
36	[5.1.0+] #BleOverrideConnection
37 ([5.0.0-5.0.2] 25)	[5.0.0+] #BleDisconnect
38 ([5.0.0-5.0.2] 26)	[5.0.0+] #BleGetConnectionState
39 ([5.0.0-5.0.2] 27)	[5.0.0+] #BleGetGattClientConditionList
40 ([5.0.0-5.0.2] 28)	[5.0.0+] #AcquireBlePairingEvent
41	[5.1.0+] #BlePairDevice
42	[5.1.0+] #BleUnpairDeviceOnBoth
43	[5.1.0+] #BleUnpairDevice
44	[5.1.0+] #BleGetPairedAddresses
45	[5.1.0+] #AcquireBleServiceDiscoveryEvent
46 ([5.0.0-5.0.2] 29)	[5.0.0+] #GetGattServices
47 ([5.0.0-5.0.2] 30)	[5.0.0+] #GetGattService
48 ([5.0.0-5.0.2] 31)	[5.0.0+] #GetGattIncludedServices
49 ([5.0.0-5.0.2] 32)	[5.0.0+] #GetBelongingService
50 ([5.0.0-5.0.2] 33)	[5.0.0+] #GetGattCharacteristics
51 ([5.0.0-5.0.2] 34)	[5.0.0+] #GetGattDescriptors
52 ([5.0.0-5.0.2] 35)	[5.0.0+] #AcquireBleMtuConfigEvent
53 ([5.0.0-5.0.2] 36)	[5.0.0+] #ConfigureBleMtu
54 ([5.0.0-5.0.2] 37)	[5.0.0+] #GetBleMtu
55 ([5.0.0-5.0.2] 38)	[5.0.0+] #RegisterBleGattDataPath
56 ([5.0.0-5.0.2] 39)	[5.0.0+] #UnregisterBleGattDataPath
57 ([5.0.0-5.0.2] 40)	[5.0.0+] #RegisterAppletResourceUserId
58 ([5.0.0-5.0.2] 41)	[5.0.0+] #UnregisterAppletResourceUserId
59 ([5.0.0-5.0.2] 42)	[5.0.0+] #SetAppletResourceUserId
60	[8.0.0+]
61	[8.0.0+]
62	[9.0.0+]
63	[9.0.0+]
64	[10.0.0+]

GetState

No input, returns an output #BtmState.

GetHostDeviceProperty

No input, returns an output #HostDeviceProperty.

This gets the previously initialized #HostDeviceProperty.

AcquireDeviceConditionEvent

No input, returns an output Event handle with EventClearMode=1.

[3.0.0+] Now returns an additional output bool.

GetDeviceCondition

Takes a type-0x1A output buffer containing a 0x368-byte struct.

SetBurstMode

Takes an input Address and a bool, no output.

SetSlotMode

Takes a type-0x19 input buffer containing a #DeviceSlotModeList, no output.

SetBluetoothMode

Takes an input #BluetoothMode, no output.

SetWlanMode

Takes an input #WlanMode, no output.

AcquireDeviceInfoEvent

No input, returns an output Event handle with EventClearMode=1.

[3.0.0+] Now returns an additional output bool.

GetDeviceInfo

Takes a type-0x1A output buffer containing a #DeviceInfoList.

AddDeviceInfo

Takes an input #DeviceInfo, no output.

RemoveDeviceInfo

Takes an input Address, no output.

IncreaseDeviceInfoOrder

Takes an input Address, no output.

LlrNotify

Takes an input Address, no output.

[9.0.0+] Takes an input Address and a s32, no output.

EnableRadio

No input/output.

DisableRadio

No input/output.

HidDisconnect

Takes an input Address, no output.

HidSetRetransmissionMode

Takes an input Address and a type-0x19 input buffer containing a #ZeroRetransmissionList, no output.

AcquireAwakeReqEvent

No input, returns an output Event handle with EventClearMode=1.

[3.0.0+] Now returns an additional output bool.

AcquireLlrStateEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

IsLlrStarted

No input, returns an output bool.

EnableSlotSaving

Takes an input bool, no output.

ProtectDeviceInfo

Takes an input Address and a bool, no output.

AcquireBleScanEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

GetBleScanParameterGeneral

Takes an input u16 ParameterId, returns a BleAdvertisePacketParameter.

The u16 must be value 0x1 or 0xFFFF.

GetBleScanParameterSmartDevice

Takes an input u16 ParameterId, returns a GattAttributeUuid.

The u16 must be value 0x2. The first 4-bytes of output is always 0 since it's not set.

StartBleScanForGeneral

Takes a BleAdvertisePacketParameter, no output.

StopBleScanForGeneral

No input/output.

GetBleScanResultsForGeneral

Takes a type-0x6 output buffer containing an array of BleScanResult, returns an output u8 total_out.

The max array entries is 10.

StartBleScanForPaired

Takes a BleAdvertisePacketParameter, no output.

StopBleScanForPaired

No input/output.

StartBleScanForSmartDevice

Takes a GattAttributeUuid, no output.

StopBleScanForSmartDevice

No input/output.

GetBleScanResultsForSmartDevice

Takes a type-0x6 output buffer containing an array of BleScanResult, returns an output u8 total_out.

The max array entries is 10.

AcquireBleConnectionEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

BleConnect

Takes an input Address, no output.

An error is thrown if the Address is already connected (listed in the BleConnectionInfo from #BleGetConnectionState). An error is thrown if 4 devices are already connected.

BleOverrideConnection

Takes an input u32, no output.

The u32 is the same as the param for #BleDisconnect.

BleDisconnect

Takes an input u32 ConnectionHandle, no output.

The u32 must match a ConnectionHandle in a BleConnectionInfo from #BleGetConnectionState. [5.1.0+] 0xFFFFFFFF is invalid.

BleGetConnectionState

Takes a type-0xA output buffer containing an array of BleConnectionInfo, returns an output u8 total_out.

Other cmds which use this internally use arraycount=4.

BleGetGattClientConditionList

Takes a type-0x1A output buffer containing a 0x74-byte struct.

AcquireBlePairingEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

BlePairDevice

Takes an input BleAdvertisePacketParameter and an u32, no output.

The u32 is the same as the param for #BleDisconnect.

BleUnpairDeviceOnBoth

Takes an input BleAdvertisePacketParameter and an u32, no output.

The u32 is the same as the param for #BleDisconnect.

BleUnpairDevice

Takes an input Address and a BleAdvertisePacketParameter, no output.

BleGetPairedAddresses

Takes a type-0xA output buffer containing an array of Address, a BleAdvertisePacketParameter, returns an output u8 total_out.

The max array entries is 10.

AcquireBleServiceDiscoveryEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

GetGattServices

Takes a type-0x6 output buffer containing an array of #GattService, an u32, returns an output u8 total_out.

The u32 is the same as the param for #BleDisconnect. The max array entries is 100.

GetGattService

Takes a type-0x1A output buffer containing a #GattService, an u32, a GattAttributeUuid, returns an output bool.

The u32 is the same as the param for #BleDisconnect. The output bool indicates whether a #GattService was returned.

Same as #GetGattServices except this only returns the #GattService which matches the input GattAttributeUuid.

GetGattIncludedServices

Takes a type-0x6 output buffer containing an array of #GattService, an u16 ServiceHandle, an u32, returns an output u8.

The u32 is the same as the param for #BleDisconnect. The max array entries is 100.

Same as #GetGattServices except this only returns #GattService entries where various checks pass with u16 fields.

The param for the output u8 is unused by the sysmodule, hence the output is always 0.

GetBelongingService

Takes a type-0x1A output buffer containing a #GattService, an u16 AttributeHandle, an u32, returns an output bool.

The u32 is the same as the param for #BleDisconnect. The output bool indicates whether a #GattService was returned.

This is similar to #GetGattIncludedServices except this only returns 1 #GattService.

GetGattCharacteristics

Takes a type-0x6 output buffer containing an array of #GattCharacteristic, an u16 ServiceHandle, an u32, returns an output u8 total_out.

The u32 is the same as the param for #BleDisconnect. The max array entries is 100.

The u16 controls which #GattCharacteristic entries to return.

GetGattDescriptors

Takes a type-0x6 output buffer containing an array of #GattDescriptor, an u16 CharHandle, an u32, returns an output u8 total_out.

The u32 is the same as the param for #BleDisconnect. The max array entries is 100.

The u16 controls which #GattDescriptor entries to return.

AcquireBleMtuConfigEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

ConfigureBleMtu

Takes an u16 mtu, an u32, no output.

The u32 is the same as the param for #BleDisconnect.

GetBleMtu

Takes an u32, returns an output u16 mtu.

The u32 is the same as the param for #BleDisconnect.

RegisterBleGattDataPath

Takes a #BleDataPath, no output.

UnregisterBleGattDataPath

Takes a #BleDataPath, no output.

RegisterAppletResourceUserId

Takes an input u32 and an AppletResourceUserId, no output.

UnregisterAppletResourceUserId

Takes an input AppletResourceUserId, no output.

SetAppletResourceUserId

Takes an input AppletResourceUserId, no output.

Cmd60

No input, returns an output Event handle with EventClearMode=1.

Cmd61

Takes a 0x44-byte input struct, no output.

This is used by hid at some point when there's new hid connections, leaving "Change Grip/Order" in the Controller_Applet with new connections also triggers it via hid at some point.

Sends a request which is then handled as follows:

• Goes through multiple arrays of Address.
  • First array:
    • Validates the Address with state, skipping it if not found.
    • Calls the SetTsi wrapper func described below, with the above Address and tsi=0xFF (Exit). If this returns false, CloseHidConnection is used with the Address.
  • Second array:
    • Validates the Address with state, skipping it if not found.
    • Uses SetBleConnectionParameter with bool=true. Then the required EventInfo is loaded, {...}.
  • Then it goes through the first array again, except here it does the following:
    • Calls the same func for validating the Address with state, skipping it if not found. It is also skipped if the u32 at Address+0x8 is value 0x3.
    • Determines what Tsi value to use, on failure CloseHidConnection is used and the loop is continued.
    • Calls the SetTsi wrapper func described below, with the Address and the above Tsi value. If this returns false, CloseHidConnection is used with the Address.
  • It then goes through various arrays again for updating state.
  • {...}

The SetTsi wrapper func is implemented as follows:

• Uses SetTsi, on failure true is returned.
• Gets the required EventInfo, returning false if a match wasn't found / EventInfo status indicates failure. True is returned for success.

Cmd62

Takes an input bool, no output.

Sends a request which is handled as follows: writes the flag into state if needed.

Cmd63

No input, returns an output bool.

This gets the flag used by #Cmd62.

Cmd64

No input/output.

Sends a request which is handled as follows: if a state field is set, another state field is set to value 1.

btm:dbg

This is "nn::btm::IBtmDebug".

This has max_sessions 6. IPC is handled by 2 threads shared with all services.

Cmd	Name
0	#AcquireDiscoveryEvent
1	#StartDiscovery
2	#CancelDiscovery
3	#GetDeviceProperty
4	#CreateBond
5	#CancelBond
6	#SetTsiMode
7	#GeneralTest
8	#HidConnect
9	[5.0.0+] #GeneralGet
10	[5.1.0+] #GetGattClientDisconnectionReason
11	[5.1.0+] #GetBleConnectionParameter
12	[5.1.0+] #GetBleConnectionParameterRequest

AcquireDiscoveryEvent

No input, returns output an Event handle with EventClearMode=1.

[3.0.0+] Now returns an additional output bool.

StartDiscovery

No input/output.

CancelDiscovery

No input/output.

GetDeviceProperty

Takes a type-0x1A output buffer containing a #DevicePropertyList.

CreateBond

Takes an input Address, no output.

CancelBond

Takes an input Address, no output.

SetTsiMode

Takes an input Address and a #TsiMode, no output.

Sends a request which is handled as follows: uses SetTsi directly with the specified params.

GeneralTest

Takes an input s32, no output.

HidConnect

Takes an input Address, no output.

GeneralGet

Takes an input u32 and a type-0x1A output buffer containing a 0x11-byte struct.

GetGattClientDisconnectionReason

Takes an input Address and an u32, returns an output bool and u16.

The bool indicates whether the cmd is successful.

GetBleConnectionParameter

Takes an input u32, returns an output bool and 3 u16s.

The bool indicates whether the cmd is successful, the output u16s are only set when this bool is set.

GetBleConnectionParameterRequest

Takes an input u32, returns an output bool and 4 u16s.

The bool indicates whether the cmd is successful, the output u16s are only set when this bool is set.

btm:sys

This is "nn::btm::IBtmSystem".

This has max_sessions 6. IPC is handled by 2 threads shared with all services.

Cmd	Name
0	#GetCore

GetCore

No input, returns an output #IBtmSystemCore.

IBtmSystemCore

This is "nn::btm::IBtmSystemCore".

Cmd	Name
0	#StartGamepadPairing
1	#CancelGamepadPairing
2	#ClearGamepadPairingDatabase
3	#GetPairedGamepadCount
4	#EnableRadio
5	#DisableRadio
6	#GetRadioOnOff
7	[3.0.0+] #AcquireRadioEvent
8	[3.0.0+] #AcquireGamepadPairingEvent
9	[3.0.0+] #IsGamepadPairingStarted

StartGamepadPairing

No input/output.

CancelGamepadPairing

No input/output.

ClearGamepadPairingDatabase

No input/output.

GetPairedGamepadCount

No input, returns an output u8.

EnableRadio

No input/output.

DisableRadio

No input/output.

GetRadioOnOff

No input, returns an output bool.

AcquireRadioEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

AcquireGamepadPairingEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

IsGamepadPairingStarted

No input, returns an output bool.

btm:u

This is "nn::btm::IBtmUser".

This was added with [5.0.0+].

This has max_sessions 6. IPC is handled by 2 threads shared with all services.

Cmd	Name
0	GetCore

GetCore

No input, returns an output #IBtmUserCore.

IBtmUserCore

This is "nn::btm::IBtmUserCore".

Cmd	Name
0	AcquireBleScanEvent
1	#GetBleScanFilterParameter
2	#GetBleScanFilterParameter2
3	StartBleScanForGeneral
4	StopBleScanForGeneral
5	GetBleScanResultsForGeneral
6	StartBleScanForPaired
7	StopBleScanForPaired
8	StartBleScanForSmartDevice
9	StopBleScanForSmartDevice
10	GetBleScanResultsForSmartDevice
17	AcquireBleConnectionEvent
18	BleConnect
19	BleDisconnect
20	BleGetConnectionState
21	AcquireBlePairingEvent
22	BlePairDevice
23	BleUnPairDevice
24	#BleUnPairDevice2
25	#BleGetPairedDevices
26	AcquireBleServiceDiscoveryEvent
27	GetGattServices
28	GetGattService
29	GetGattIncludedServices
30	#GetBelongingGattService
31	GetGattCharacteristics
32	GetGattDescriptors
33	AcquireBleMtuConfigEvent
34	ConfigureBleMtu
35	GetBleMtu
36	RegisterBleGattDataPath
37	UnregisterBleGattDataPath

AcquireBleScanEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

This is similar to the btm cmd.

GetBleScanFilterParameter

Takes an input u16, returns a BleAdvertisePacketParameter.

This is the same as #GetBleScanParameterGeneral.

GetBleScanFilterParameter2

Takes an input u16, returns a GattAttributeUuid.

This is the same as #GetBleScanParameterSmartDevice.

StartBleScanForGeneral

Takes a PID, a BleAdvertisePacketParameter, an AppletResourceUserId, no output.

This is similar to the btm cmd.

StopBleScanForGeneral

No input/output.

This is similar to the btm cmd.

GetBleScanResultsForGeneral

Takes a PID, a type-0x6 output buffer containing an array of BleScanResult, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

StartBleScanForPaired

Takes a PID, a BleAdvertisePacketParameter, an AppletResourceUserId, no output.

This is similar to the btm cmd.

StopBleScanForPaired

No input/output.

This is similar to the btm cmd.

StartBleScanForSmartDevice

Takes a PID, a GattAttributeUuid, an AppletResourceUserId, no output.

This is similar to the btm cmd.

StopBleScanForSmartDevice

No input/output.

This is similar to the btm cmd.

GetBleScanResultsForSmartDevice

Takes a PID, a type-0x6 output buffer containing an array of BleScanResult, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

AcquireBleConnectionEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

This is similar to the btm cmd.

BleConnect

Takes a PID, an Address, an AppletResourceUserId, no output.

This is similar to the btm cmd.

BleDisconnect

Takes an input u32, no output.

This is similar to the btm cmd.

BleGetConnectionState

Takes a PID, a type-0xA output buffer containing an array of BleConnectionInfo, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

AcquireBlePairingEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

This is similar to the btm cmd.

BlePairDevice

Takes an input BleAdvertisePacketParameter and an u32, no output.

This is similar to the btm cmd.

BleUnPairDevice

Takes an input BleAdvertisePacketParameter and an u32, no output.

This is similar to the btm cmd.

BleUnPairDevice2

Takes an input Address and a BleAdvertisePacketParameter, no output.

This is similar to the btm cmd.

BleGetPairedDevices

Takes a type-0xA output buffer containing an array of Address, a BleAdvertisePacketParameter, returns an output u8 total_out.

This is the same as the btm cmd.

AcquireBleServiceDiscoveryEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

This is similar to the btm cmd.

sdknso will Abort if the output u8 is value 0.

GetGattServices

Takes a PID, a type-0x6 output buffer containing an array of #GattService, an u32, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

GetGattService

Takes a PID, a type-0x1A output buffer containing a #GattService, an u32, a GattAttributeUuid, an AppletResourceUserId, returns an output bool.

This is similar to the btm cmd.

GetGattIncludedServices

Takes a PID, a type-0x6 output buffer containing an array of #GattService, an u16, an u32, an AppletResourceUserId, returns an output u8.

This is similar to the btm cmd.

The param for the output u8 is unused by the sysmodule, hence the output is always 0. However, a sdknso func which calls the nn::btm::* func for this expects this u8 to be set.

GetBelongingGattService

Takes a PID, a type-0x1A output buffer containing a #GattService, an u16, an u32, an AppletResourceUserId, returns an output bool.

This is similar to the btm cmd.

GetGattCharacteristics

Takes a PID, a type-0x6 output buffer containing an array of #GattCharacteristic, an u16, an u32, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

GetGattDescriptors

Takes a PID, a type-0x6 output buffer containing an array of #GattDescriptor, an u16, an u32, an AppletResourceUserId, returns an output u8 total_out.

This is similar to the btm cmd.

AcquireBleMtuConfigEvent

No input, returns an output bool and an Event handle with EventClearMode=1.

This is similar to the btm cmd.

ConfigureBleMtu

Takes a PID, an u16, an u32, an AppletResourceUserId, no output.

This is similar to the btm cmd.

sdknso will Abort if the user-specified u16 is <0x18 or >0x200 (this doesn't apply to the btm cmd).

GetBleMtu

Takes a PID, an u32, an AppletResourceUserId, returns an output u16.

This is similar to the btm cmd.

RegisterBleGattDataPath

Takes a PID, a #BleDataPath, an AppletResourceUserId, no output.

This is similar to the btm cmd.

UnregisterBleGattDataPath

Takes a PID, a #BleDataPath, an AppletResourceUserId, no output.

This is similar to the btm cmd.

BtmState

This is "nn::btm::BtmState". This is an u32 enum.

BluetoothMode

This is "nn::btm::BluetoothMode". This is an u32 enum.

WlanMode

This is "nn::btm::WlanMode". This is an u32 enum.

TsiMode

This is "nn::btm::TsiMode". This is an u32 enum.

HostDeviceProperty

This is "nn::btm::HostDeviceProperty". This is a 0x2A-byte struct.

Offset	Size	Description
0x0	0x9	Same as AdapterProperty+0x0.
0x9	0x1F	Same as AdapterProperty+0x9.
0x28	0x1	Always zero.
0x29	0x1	Same as AdapterProperty+0x102.

DeviceSlotModeList

This is "nn::btm::DeviceSlotModeList". This is a 0x64-byte struct.

DeviceInfoList

This is "nn::btm::DeviceInfoList". This is a 0x3C4-byte struct.

Offset	Size	Description
0x0	0x1	Total entries.
0x1	0x3	Padding
0x4	0xA*60(0x3C0)	Array of #DeviceInfo.

DeviceInfo

This is "nn::btm::DeviceInfo". This is a 0x60-byte struct.

DevicePropertyList

This is "nn::btm::DevicePropertyList". This is a 0x268-byte struct.

ZeroRetransmissionList

This is "nn::btm::ZeroRetransmissionList". This is a 0x11-byte struct.

GattService

This is "nn::btm::user::GattService". This is a 0x24-byte struct.

Offset	Size	Description
0x0	0x4
0x4	0x14	GattAttributeUuid
0x18	0x2	Handle
0x1A	0x2
0x1C	0x2	InstanceId
0x1E	0x2	EndGroupHandle
0x20	0x1	PrimaryService flag
0x21	0x3	Padding

GattCharacteristic

This is "nn::btm::user::GattCharacteristic". This is a 0x24-byte struct.

Offset	Size	Description
0x0	0x4
0x4	0x14	GattAttributeUuid
0x18	0x2	Handle
0x1A	0x2
0x1C	0x2	InstanceId
0x1E	0x1	Properties
0x1F	0x5

GattDescriptor

This is "nn::btm::user::GattDescriptor". This is a 0x20-byte struct.

Offset	Size	Description
0x0	0x4
0x4	0x14	GattAttributeUuid
0x18	0x2	Handle
0x1A	0x6

BleDataPath

This is "nn::btm::user::BleDataPath". This is a 0x18-byte struct with 4-byte alignment.

Offset	Size	Description
0x0	0x1
0x1	0x3	Padding
0x4	0x14	GattAttributeUuid