the "device is used by another application" is something that plagued early windows drivers , I remember it all too well 🤣
I just tested the MPU drivers with my 98SE setup -
- Music Quest / Roland embedded windows driver: both DOS and Windows applications work fine as long as only one application uses the MPU
- Twelve Tone Systems driver: it can only be used under windows and more than one applications can use it - if a DOS application tries to use the MPU you get this message "MPU is used by Windows"
- GSPanel driver: it can be used by more than one windows application and it will work under DOS but when you return to windows you will get nothing out of the MPU until you restart windows
So basically for gaming one should stick to the MQ/Roland driver that comes with windows and for music creation or windows-only usage one of the multiport drivers can be used.
This is not a PCMIDI thing, same behavior happens with real Roland mpus.
I will add this info to the site , I admit I never bothered running DOS stuff under windows so I learned (or re-learned after I have forgotted) something 🤣
if one needs to remove the multiport drivers it needs to be done by editing SYSTEM.INI (easily accessible by running SYSEDIT under 9x)
On [386 Enh] section remove the line containing:
mpu.drv (for the GSPanel driver)
vmpud.386 (for the TTS driver)
then at the end of SYSTEM.INI there is a [mpu.drv] section, this needs to be removed completely
after restart you can use the "add new hardware" in control panel to add the Music Quest or Roland driver back to the system.
the multiport drivers are INI-based so they don't appear in device manager.