58 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			58 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # Commodore 64
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| 
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| a home computer with a synthesizer-grade sound chip of which people took decades to master.
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| 
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| very popular in Europe and mostly due to the demoscene, which stretched the machine's limbs to no end.
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| 
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| # effects
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| 
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| - `10xx`: change wave. the following values are accepted:
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|   - `00`: nothing
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|   - `01`: triangle
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|   - `02`: saw
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|   - `03`: triangle and saw
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|   - `04`: pulse
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|   - `05`: pulse and triangle
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|   - `06`: pulse and saw
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|   - `07`: pulse and triangle and saw
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|   - `08`: noise
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| - `11xx`: set coarse cutoff. `xx` may be a value between 00 to 64.
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|   - **this effect only exists for compatibility reasons, and its use is discouraged.**
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|   - use effect `4xxx` instead.
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| - `12xx`: set coarse duty cycle. `xx` may be a value between 00 to 64.
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|   - **this effect only exists for compatibility reasons, and its use is discouraged.**
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|   - use effect `3xxx` instead.
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| - `13xx`: set resonance. `xx` may be a value between 00 and 0F.
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| - `14xx`: set filter mode. the following values are accepted:
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|   - `00`: filter off
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|   - `01`: low pass
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|   - `02`: band pass
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|   - `03`: low+band pass
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|   - `04`: high pass
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|   - `05`: band reject/stop/notch
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|   - `06`: high+band pass
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|   - `07`: all pass
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| - `15xx`: set envelope reset time.
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|   - this is the amount of ticks the channel turns off before a note occurs in order to reset the envelope safely.
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|   - if `xx` is 0 or higher than the song speed, the envelope will not reset.
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| - `1Axx`: disable envelope reset for this channel.
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| - `1Bxy`: reset cutoff:
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|   - if `x` is not 0: on new note
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|   - if `y` is not 0: now
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|   - this effect is not necessary if the instrument's cutoff macro is absolute.
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| - `1Cxy`: reset duty cycle:
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|   - if `x` is not 0: on new note
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|   - if `y` is not 0: now
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|   - this effect is not necessary if the instrument's duty macro is absolute.
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| - `1Exy`: change additional parameters.
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|   - `x` may be one of the following:
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|     - `0`: attack (`y` from 0 to F)
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|     - `1`: decay (`y` from 0 to F)
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|     - `2`: sustain (`y` from 0 to F)
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|     - `3`: release (`y` from 0 to F)
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|     - `4`: ring modulation (`y` is 0 or 1)
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|     - `5`: oscillator sync (`y` is 0 or 1)
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|     - `6`: disable channel 3 (`y` is 0 or 1)
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| - `3xxx`: set duty cycle. `xxx` range is 000-FFF
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| - `4xxx`: set cutoff. `xxx` range is 000-7FF.
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