MSX Assembly Page

JVC MSX MIDI interface

The JVC MSX MIDI interface is based on the Motorola MC6850 ACIA with a 2 MHz clock crystal. It also provides a DIN sync input. Electro Music Research also manufactured this interface for several other platforms, like the ZX Spectrum, Amstrad CPC and BBC Micro.

Port Description
#00 DIN sync input. Bit 0: stop / start, bit 1: clock pulse.
#02 MC6850 ACIA command / status. Note: use /64 divider.
#03 MC6850 ACIA data

The I/O ports are mirrored at #08-#0B.

Thanks go to gflorez for providing port and divider information.