SETOPL4
-------

Format:      SETOPL4 [/R] [/?] [/On] [/Fn] [/Wn] [/A] [/P] [/S] [/C]

Purpose:     To change de current OPL4 mode and/or the current volume.

Use:         /R will reset some of the registers from the OPL4. This may be
             nessecery when the registers of the OPL4 contain wrong values.
             The MIX control of the OPL4 is not reseted by this option.
             It is not clear yet wich registers are reseted by this option.

             If /? is given then the program will show the build in help and
             will return to DOS. This means that options that are given
             after /? will be ignored.

             /On will change or display the current OPL mode.
             The 'n' stands for the following options:

             /O2   this will put the OPL4 in the OPL2 mode
             /O3   this will put the OPL4 in the OPL3 mode
             /O4   this will put the OPL4 in the OPL4 mode
             /O?   this will display the current OPL mode

             The OPL4 has no OPL1 mode because the OPL2 mode is 100%
             compatible with the OPL1 mode.
             The OPL2 mode can be used when you want to use your OPL4 instead
             of the MSX-AUDIO (only the FM part).

             /Fn is used to change the volume of the FM part of the OPL4
             /Wn is used to change the volume of the PCM part of the OPL4

             For 'n' you can use a volume from 0 until 7.
             0 is no sound at all.
             7 is the loudest.

             The options /Fn and /Wn change the volume in the MIX unit
             of the OPL4. It is a master volume. Most of the now existing
             OPL4 programs don't use the master volume. This means that
             the volume wich is set by SETOPL4 wil not be changed by most
             of the programs. So far as I know only the N.O.P. modplayer
             changes the master-volume.

	     /A activates the MSX-AUDIO (POKE -54,35). This can be used for
	     japanese games or programs that suport MSX-AUDIO. It is necessary
	     to put a jumper on the MOONSOUND card or change the ports in the
	     program it self to use the OPL4 for replaying the MSX-AUDIO data. 
			    
	     Warning!!! DOS2.XX will not be able to use the Memory Mapper
	     when /A is applied. Use this option only when necessary!! 

	     /Pnnn play sample. The opl4 will play a sample if you put a value
	     behind /P.The value must be decimal.
	     This must be a value between 0-511. You will here 'ROM' sample's
	     from 0-383 and 'SRAM' sample's form 384 to 511.
	     
	     The opl4 must not be in the opl2 mode, because if it is you
	     won't here a thing.
	     
	     /S Stop's all sample's from channel 1 untill channel 24. 
	     
	     /C Create MTN (Moonblaster tone) file. An MTN file will be
		created if this option is given. The tone is selected
		by the sample play option. for example:
		
		A:\>SETOPL4 /p385/c
		
		This will cause that sram tone number 2 will be saved to disk.
		You will here the sample and then you give it a appp... file 
		and tone name.
		
		Rom samples can't be saved into the MTN format because the MTN
		format doesn't support the 12 bit samples.
	      
	     If an incorrect option or value is given then the program will 
	     be aborted.

Examples:

             A:\>SETOPL4 /F4 /W7 /O4

             This will change de FM volume to 4, the PCM volume to 7 and the
             OPL mode to the OPL4 mode.
