NEC POWERMATE VP Manual page 231

JUMPER FUNCTIONS
MIDI Base I/O Address
D-4 Sound Board Jumper Settings
The following sections describe the sound board jumper
functions and settings.
Jumper MSEL sets the base I/O address for the MPU-401
UART MIDI interface. Two base I/O addresses are
available:
n
300H
n
330H (factory setting).
Base I/O address settings of the MIDI interface