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Posted: **Sun Jun 08, 2008 11:41 pm**

I'm trying to setup the bordercolor for the VGA using BIOS 0x10 services, but QEMU and Bochs does not show the border color. Anyone knows if Qemu or Bochs emulate the overscan color?

Here's the code:

Code: Select all

setupvid:
 	push	ax
 	push	bx
 	xor	bx, bx
 	mov	ax, 0x1001
 	mov	bh, 0x11		;blue
 	int	10h
 	pop	bx
 	pop	ax
	ret

Thanks.

Posted: **Mon Jun 09, 2008 3:10 am**

They don't, because there is no border visible around the "screen".

Border color was once visible on CRTs. Nowadays TFTs don't show the border. Like Bochs (or any other emulator I know).

Posted: **Mon Jun 09, 2008 8:09 am**

I had a quick look at Bochs' source - Overscan is emulated, but it doesn't show for the reasons mentioned.
It does mean you can set it and read it as expected. The result is just not visible.

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Bochs / QEMU VGA Compatibility

Bochs / QEMU VGA Compatibility