44 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			44 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | # Virtual Boy
 | ||
|  | 
 | ||
|  | a "portable" video game console made by Nintendo in the '90's. | ||
|  | 
 | ||
|  | it supposedly was the beginning of virtual reality... nah, instead it failed to sell well because you use it for 15 minutes and then you get a headache. | ||
|  | 
 | ||
|  | its sound generation chip is called Virtual Sound Unit (VSU), a wavetable chip that is a lot like PC Engine, but unlike that, the waves are twice as tall, it doesn't go too low in terms of frequency (~D-2), and the last channel (yep, it has 6 channels) is a noise one. | ||
|  | 
 | ||
|  | additionally, channel 5 offers a modulation/sweep unit. the former is similar to FDS' but has much reduced speed control. | ||
|  | 
 | ||
|  | # effects
 | ||
|  | 
 | ||
|  | - `10xx`: set waveform. | ||
|  | - `11xx`: set noise length (0 to 7). | ||
|  |   - only in the noise channel. | ||
|  | - `12xy`: setup envelope. | ||
|  |   - `x` determines whether envelope is enabled or not. | ||
|  |     - 0: disabled | ||
|  |     - 1: enabled | ||
|  |     - 3: enabled and loop | ||
|  |     - yeah, the value 2 isn't useful. | ||
|  |   - `y` sets the speed and direction. | ||
|  |     - 0-7: down | ||
|  |     - 8-F: up | ||
|  | - `13xy`: setup sweep. | ||
|  |   - `x` sets the speed. | ||
|  |     - 0 and 8 are "speed 0" - sweep is ineffective. | ||
|  |   - `y` sets the shift (0 to 7). | ||
|  |     - 8 and higher will mute the channel. | ||
|  |   - only in channel 5. | ||
|  | - `14xy`: setup modulation. | ||
|  |   - `x` determines whether it's enabled or not. | ||
|  |     - 0: disabled | ||
|  |     - 1: enabled | ||
|  |     - 3: enabled and loop | ||
|  |     - 2 isn't useful here either. | ||
|  |   - `y` sets the speed. | ||
|  |     - 0 and 8 are "speed 0" - modulation is ineffective. | ||
|  |     - no, you can't really do Yamaha FM using this. | ||
|  |   - only in channel 5. | ||
|  | - `15xx`: set modulation wave. | ||
|  |   - `xx` points to a wavetable. it should have a height of 255. | ||
|  |   - this is an alternative to setting the modulation wave through the instrument. |