[comp.sys.mac.hardware] Mac LC -> VGA

colin@lingua.cltr.uq.OZ.AU (Colin Canfield) (03/21/91)

The pinouts on the LC video port have the same name as on a VGA monitor, I 
have also heard that the LC supports VGA. If I was to make a conversion 
cable that just swapped the appropriate pins does anyone if this will work
correctly?

Thanks in advance, Colin

colin@lingua.cltr.uq.oz.au

prw@Apple.COM (Paul Wenker) (03/23/91)

In article <1991Mar21.075841.1396@lingua.cltr.uq.OZ.AU> colin@lingua.cltr.uq.OZ.AU (Colin Canfield) writes:
>The pinouts on the LC video port have the same name as on a VGA monitor, I 
>have also heard that the LC supports VGA. If I was to make a conversion 
>cable that just swapped the appropriate pins does anyone if this will work
>correctly?

The latest version of Mac Tech Note #144 describes how to connect a VGA
monitor to the Mac LC.  In short, this is how to make the cable...

LC Pin		VGA Pin		Signal name
------		-------		-----------
1		6		Red ground
2		1		Red video signal
5		2		Green video signal
6		7		Green ground
9		3		Blue video signal
13		8		Blue ground
15		13		/HSYNC
12		14		/VSYNC
14		10		HSYNC ground
7, 10		nc		SENSE1 & SENSE2 tied together

The LC supports 640x480x16 on a VGA monitor, or 640x480x256 if you have
512k VRAM.

NOTE: The Tech Note warns that some low impedence VGA monitors will not
work with the Mac LC.


-Paul Wenker
-Apple Computer, Inc.

chaos@applelink.apple.com (Rich Collyer) (03/23/91)

In article <1991Mar21.075841.1396@lingua.cltr.uq.OZ.AU> 
colin@lingua.cltr.uq.OZ.AU (Colin Canfield) writes:
> The pinouts on the LC video port have the same name as on a VGA monitor, 
> I have also heard that the LC supports VGA. If I was to make a conversion 
> cable that just swapped the appropriate pins does anyone if this will 
> work correctly?

The Mac LC does support VGA.  The documentation on it is in the February 
1991 version of Technical Note 144 from Developer Technical Support