| Namespace | Windows.Devices.Midi2.Transports.Bluetooth |
|---|---|
| Type Name | MidiBluetoothDeviceInformation |
| Type | WinRT Runtime Class |
| IDL | MidiBluetoothDeviceInformation.idl |
Returned by MidiBluetoothTransportManager.GetAvailableDevices and MidiBluetoothTransportManager.GetDevice.
| Property | Description |
|---|---|
BluetoothDeviceId |
The device’s Bluetooth address as twelve hex digits, and the key for every operation in this namespace. It isn’t a Windows device interface id |
BluetoothAddress |
The same address as a number, to match up with the Windows.Devices.Bluetooth APIs |
Name |
The name the device reports. Empty until the device has been heard long enough to learn it |
SelectedProtocol |
The MidiBluetoothProtocol in use. Unknown until the device is connected, because finding out means reading the device’s characteristics |
IsConnected |
True when the device is connected to this PC and its MIDI endpoint is ready. It stays false while a connection is still being set up |
ConnectionState |
A MidiBluetoothConnectionState that says how far along the device is. Connecting happens in the background, and a device someone asked for keeps being tried until it shows up, so this tells you more than IsConnected can |
IsPaired |
True when the device is paired with this PC. Bluetooth MIDI doesn’t require pairing |
RequiresPairing |
True when the device won’t provide its MIDI service until the connection is authenticated. A device’s advertising never says this, so it’s only known after trying to connect. While it’s true, the service stops trying the device, because every try brings up another Windows pairing prompt |
IsPresent |
True while the device is advertising. Bluetooth MIDI devices go to sleep quickly to save power, so a device that isn’t present is usually asleep, not gone |
SignalStrengthDecibelMilliwatts |
The signal strength of the most recent advertisement, in dBm. A connected device stops advertising, so then this is out of date |
LastSeenAgo |
How long ago the device was last heard. Means nothing when HasBeenSeen is false |
HasBeenSeen |
False when the radio has never heard this device at all. This is how you tell a paired device that Windows remembers from one that was heard a long time ago |
HasEndpoint |
True when a MIDI endpoint exists for this device |
EndpointDeviceId |
The MIDI endpoint’s device interface id, if there is one |
EndpointDeviceInstanceId |
The endpoint’s instance id, which is what an endpoint customization matches on |
MessagesReceived |
How many messages have been received from the device |
MessagesSent |
How many messages have been sent to the device |
PacketsReceived |
How many Bluetooth packets have been received, counted before they’re decoded. If packets keep climbing while MessagesReceived stays at zero, the device is sending something this transport can’t decode. If both are zero, it isn’t sending anything at all |
PacketsSent |
How many Bluetooth packets have been sent |
TimestampSource |
A MidiBluetoothTimestampSource that says whether the device’s own timestamps are used, or the time each message arrived is used instead |
ConnectionInterval |
The time between data exchanges that the PC and the device agreed on. Zero when not connected |
LastConnectError |
The transport’s own wording for the most recent connection failure. It’s more specific than the error code |
LastConnectErrorCode |
A MidiBluetoothDeviceConnectErrorCode that says why the last connection attempt failed |
LastConnectErrorHResult |
The HRESULT error number behind that failure |
LastSendErrorHResult |
The HRESULT error number from the most recent failed send |
OfflineRetentionSeconds |
How long this device’s endpoint stays after the device goes offline, as seconds or a named MidiBluetoothOfflineRetention value. This is the device’s own setting, so it can be UseTransportDefault |
EffectiveOfflineRetentionSeconds |
The same, after the transport setting is applied, so it’s never UseTransportDefault. Show this one to people |
Check LastConnectErrorCode after you ask for a connection. Connecting happens in the background, long after ConnectDeviceAsync returns. So a failure during that work shows up here, not in the response.
The endpoint’s native data format isn’t reported here. Read it from the endpoint itself, with MidiEndpointDeviceInformation and Windows.Devices.Midi2.Enumeration.MidiEndpointNativeDataFormat.
Windows MIDI Services is an open source project with all source available on GitHub. We have a great community on Discord as well. Between GitHub and Discord, you should find the information you are looking for.
