6.5 MIDI direct output

sound driver is a sound generator that produces MIDI messages, it can also be produced by giving MIDI messages directly without creating sequence data. This command is an interface for this purpose, and has a message block given to the sound driver as a parameter.
The message block is a 4-byte data block with the parameters at the beginning of pronunciation added to the MIDI message, and is structured as shown below.



Support for actual MIDI events


CMD value	corresponding MIDI Event
0	(80h-8Fh) Note Off Event
1	(90h-9Fh) Note On Event
2	(A0h-AFh) After Touch
3	(B0h-BFh) Control Change
4	(C0h-CFh) Program Change
5	(D0h-DFh) Channel Pressure
6	(E0h-EFh) Pitch Wheel
7	(F0h-FFh) System Massage

6.5.1 Usage

Issue the “MIDI Direct Control (09h)” command with the 4-byte message block as parameters P1, P2, P3, and P4. However, since there are advantages and disadvantages as follows, please choose a better method after consulting with the sound creator.



  Advantages 
・ Real-time control that cannot be previously stored in sequence data is possible.
・ No need to create data from sequence creation to compression.
-Since compression / decompression processing can be omitted, no additional processing is required. 

Cons
Instead of being able to do anything, you may need to build a sophisticated program with a good understanding of the contents. (If you do not know the relationship between the MIDI channel and the corresponding tone, DSP program and mixer specifications, etc., you will not be able to use it properly, so you need to coordinate with the sound creator.)