Setting Up OpenMenu
GameID vs DisplayID
There are 2 main ways the VMUPro can determine which game you have launched on the Dreamcast:
DisplayID
Most useful when using your dreamcast with the original Sega GDROM drive. This method identifies most games based on their unique VMU LCD Graphics. This method is not foolproof, however, and so it is recommended, where possible to use GameID.
GameID
GameID is when a custom loader such as OpenMenu (see below) sends a game's disk ID directly to the VMUPro when the game is launched. This is the most accurate approach, and available when using Optical Disk Emulators (ODEs) such as MODE or GDEmu.
Setting Up OpenMenu (or updating it)
The simplest way to get started is to use GDMenu Card Manager, a tool which transfers your games to SD card with a copy of OpenMenu. https://github.com/sonik-br/GDMENUCardManager Connect your ODE's microSD card to your computer. (Not the one from your VMUPro) Extract the GDMenuCardManager .zip file and run GDMenuCardManager.exe
Select your SD Drive from the top left, and press the Refresh button. If you already have files on your SD card, the list will update, if not, drag some games onto the main window (Or use the + button if drag & drop is not supported by your OS). Tip: Drag the whole game folder into the GDMenu Card Manager window, not individual files. Be sure to select "openMenu" from the toggle switches at the top right hand side.
Don't hit save yet! (But don't worry if you already have.)
GDMenu Card Manager must be updated to the latest OpenMenu to support the VMUPro. This only has to be done one time, and may be automated in the future. Download OpenMenu .zip from here: https://github.com/sbstnc/openmenu/releases
Find the 1ST_READ.BIN file inside the the OpenMenu .zip and copy into the folder GDMenuCardManager\tools\openMenu\menu_data\
For example if you extracted GDMenuCardManager to c:\games\cardmanager\ then you would replace c:\games\cardmanager\tools\openMenu\menu_data\1ST_READ.BIN with the new one.
Q: What happens if I miss this step? A: The VMUPro will not receive GameID commands from OpenMenu, and will instead fall back to DisplayID.
Finally, hit the big Save Changes button, and your games + GameID-enabled OpenMenu will be written to your SD card.
Q: My "Save Changes" button is not enabled! A: Make a small change to your Games List, such as changing the order, or adding and removing a game. This re-enables the Save Changes button.
Q: Sometimes my VMUPro changes VMCs when I exit OpenMenu A: This is by design! When you exit OpenMenu, it sends the GameID of the highlighted entry so that you can manage saves for that game.
Q: Is this tutorial available in video format? A: Active community contributor Derek Pascarella has an in-depth tutorial on installing and updating GDMenuCardManager: https://www.youtube.com/watch?v=QjUgXkdiVq4