If you want to send MIDI commands to external devices (such as keyboards, guitar processors, drum machines, etc.) you can set up MIDI commands that can be saved to songs. Please note that this feature is only available for devices running Android Marshmallow or later and have the built in MIDI feature. Older and non-compatible devices will not see this option in the menu or will be told their device is not compatible - sorry!
To connect a MIDI device to OpenSongApp, open the right hand options menu and select the 'MIDI' category. Click on 'Connect Bluetooth' or 'Connect USB device' depending on the MIDI device you have. Please note that the app can only connect to one device directly. You can, however, connect multiple MIDI devices together using their OUT/THRU ports and send commands via different MIDI channels to trigger different devices.
Click on the 'Scan' button to list any available devices. Please note that the Bluetooth scan only searches for MIDI Bluetooth devices. Depending on the device you use, you may need to activate pairing mode on the device, or run the scan a few times to pick up pairing signals. USB scan will immediately show any devices already connected (including already connected Bluetooth devices). Once you see your device in the list, click on it. The app will then initiate the connection and give you the opportunity to send a test note (this sends middle C, so will only be heard on MIDI playback devices). Close this window once you have connected your device.
To build MIDI commands to save with the current song, select 'Edit song commands' from the MIDI menu.
On this screen you can add various standard MIDI messages using the drop down menus. You will also see any current MIDI commands saved with the song.
Choose an appropriate command (options include: Note on/off, Program change, Controller change, MSB and LSB), set the desired MIDI channel and appropriate values. Clicking on the 'Test' button will send the currently edited MIDI command to your device. If you are happy with this, click on the 'Add' button to save it to the song and will be added to the bottom of the MIDI command list.
Please note that multiple MIDI messages get sent in the order they appear in the list. To test an item in the MIDI command list, click on it. To delete a command, long click on it.
Click on the green tick at the top of the window to save the MIDI commands to the song.
To automatically send MIDI commands stored with songs, switch the 'Auto send midi' button to on in the MIDI menu. The MIDI messages will be sent automatically to connected devices when the song is loaded.
If you want to manually click on MIDI events during a song, click on the 'Send MIDI' option in the MIDI menu. You can also assign a custom quick launch button to bring up this window.