36 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # PC Speaker
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| 
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| 40 years of one square beep - and still going! single channel, no volume control...
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| 
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| ## real output
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| 
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| so far this is the only chip in Furnace which has a real hardware output option.
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| to enable it, select file > configure chip... > PC Speaker > Use system beeper.
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| 
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| be noted that this will only work on Linux as Windows does not provide any user-space APIs to address the PC speaker directly!
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| 
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| you may configure the output method by going in Settings > Emulation > PC Speaker strategy:
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| 
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| - `evdev SND_TONE`: uses input events to control the beeper.
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|   - requires write permission to `/dev/input/by-path/platform-pcspkr-event-spkr`.
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|   - is not 100% frequency-accurate as `SND_TONE` demands frequencies, but Furnace uses raw timer periods...
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| - `KIOCSOUND on /dev/tty1`: sends the `KIOCSOUND` ioctl to control the beeper.
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|   - may require running Furnace as root.
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| - `/dev/port`: writes to `/dev/port` to control the beeper.
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|   - requires read/write permission to `/dev/port`.
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| - `KIOCSOUND on standard output`: sends the `KIOCSOUND` ioctl to control the beeper.
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|   - requires running Furnace on a TTY.
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| - `outb()`: uses the low-level kernel port API to control the beeper.
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|   - requires running Furnace as root, or granting it `CAP_SYS_RAWIO` to the Furnace executable: `sudo setcap cap_sys_rawio=ep ./furnace`.
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| 
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| real hardware output only works on BIOS/UEFI (non-Mac) x86-based machines! attempting to do this under any other device **will not work**, or may even brick the device (if using `/dev/port` or `outb()`)!
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| oh, and of course you also need the beeper to be present in your machine. some laptops connect the beeper output to the built-in speakers (or the audio output jack), and some other don't do this at all.
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| 
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| ## effects
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| 
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| ha! effects...
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| 
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| ## info
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| 
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| this chip uses the [Beeper](../4-instrument/beeper.md) instrument editor.
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