Re: My Apple IIGS is back

["Michael J. Mahon" <mjmahon@aol.com>]

limtc wrote:
> Hi Michael - this is not what I mean or tested. What you say is
> exactly correct. But in ROM 3 GS connected to the same TV, whenever
> you enter into text mode, it will switch to crisp monochrome text
> within a second or 2, regardless of control panel texting. In ROM 1
> GS, it will not.

I understand.

The reason for this is that the ROM 3 provides better isolation
for the 3.58MHz color burst when it is switched off.

Your monitor is very sensitive to the presence of color burst
once it has been detected, so, even after the ROM 1 switches off
the color burst, enough "leaks through" to keep your monitor in
color mode.

> On 4锟斤拷20锟斤拷, 锟斤拷锟斤拷8时49锟斤拷, "Michael J. Mahon" <mjma...@aol.com> wrote:
> 
> 
>>NTSC composite color processing generally does not preserve luminnance
>>information beyond about 3MHz, so 80-column text is usually unreadable.
>>
>>In monochrome mode, there is more flexibility and your monitor may
>>make use of extended luminance bandwidth to render 80-column text
>>well.
>>
>>This is standard behavior--a monitor cannot switch quickly (within
>>a frame) from color to monochrome and back.
>>
>>The Apple II generates a color video signal anytime that graphics
>>are displayed, even if the screen is "mixed".


-- 

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

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