63 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # Yamaha YM2413/OPLL
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| 
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| the YM2413, otherwise known as OPLL, is a cost-reduced FM synthesis sound chip, based on the Yamaha YM3812 (OPL2). thought OPL was downgraded enough? :p
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| 
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| OPLL also spawned a few derivative chips, the best known of these is:
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| - the famous Konami VRC7. used in the Japan-only video game Lagrange Point, it was **another** cost reduction on top of the OPLL! this time just 6 channels...
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| - Yamaha YM2423, same chip as YM2413, just a different patch set
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| - Yamaha YMF281, ditto
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| 
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| # technical specifications
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| the YM2413 is equipped with the following features:
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| 
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| - 9 channels of 2 operator FM synthesis
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| - A drum/percussion mode, replacing the last 3 voices with 5 rhythm channels
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| - 1 user-definable patch (this patch can be changed throughout the course of the song)
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| - 15 pre-defined patches which can all be used at the same time
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| - Support for ADSR on both the modulator and the carrier
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| - Sine and half-sine based FM synthesis
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| - 9 octave note control
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| - 4096 different frequencies for channels
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| - 16 unique volume levels (NOTE: Volume 0 is NOT silent.)
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| - Modulator and carrier key scaling
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| - Built-in hardware vibrato support
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| 
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| # effects
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| 
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| - `11xx`: set feedback of channel.
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| - `12xx`: set operator 1 level.
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| - `13xx`: set operator 2 level.
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| - `16xy`: set multiplier of operator.
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|   - `x` is the operator (1 or 2).
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|   - `y` is the mutliplier.
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| - `18xx`: toggle drums mode.
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|   - 0 disables it and 1 enables it.
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|   - only in drums system.
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| - `19xx`: set attack of all operators.
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| - `1Axx`: set attack of operator 1.
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| - `1Bxx`: set attack of operator 2.
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| - `50xy`: set AM of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` determines whether AM is on.
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| - `51xy` set SL of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` is the value.
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| - `52xy` set RR of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` is the value.
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| - `53xy`: set VIB of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` determines whether VIB is on.
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| - `54xy` set KSL of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` is the value.
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| - `55xy` set EGT of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` determines whether EGT is on.
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| - `56xx`: set DR of all operators.
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| - `57xx`: set DR of operator 1.
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| - `58xx`: set DR of operator 2.
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| - `5Bxy`: set KSR of operator.
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|   - `x` is the operator (1-2). a value of 0 means "all operators".
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|   - `y` determines whether KSR is on. | 
