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Re: NTSC stops to exist on Apple //e?



"Don Bruder" <dakidd@sonic.net> wrote in message 
news:44e647a9$0$96204$742ec2ed@news.sonic.net...
> In article <7VjFg.10445$kO3.8898@newssvr12.news.prodigy.com>,
> "Bryan Parkoff" <nospam@nospam.com> wrote:
>
>> Hello,
>>
>>     What if NTSC monitor and television become obsolete?  The 
>> manufacturer
>> stops making NTSC.  It is going to replace HDTV.  How can we overcome 
>> NTSC
>> problem?  The answer is to use VGA monitor.
>>
>>     We have enough information what we use schematic for Apple //e's
>> motherboard.  We should be able to redesign Apple //e's motherboard. 
>> NTSC
>> circuit will be removed to replace VGA circuit.  Apple II 8-bit slots can 
>> be
>> replaced to PCI slots.  16MB RAM will be built in motherboard.  It is to 
>> be
>> 658C16 MPU.
>>
>>     Video RAM will be located higher RAM above $E0 bank.  $400-$BFF for 
>> TEXT
>> and $2000-$5FFF for GRAPHIC ceases to exist and they will never be 
>> directed
>> to video.  We may use special routines to read video data from $400-$BFF 
>> for
>> TEXT and $2000-$5FFF for GRAHPIC before they are translated to video RAM 
>> in
>> $E0 bank.  Games in 658C16 code can be written to fill the RAM memory 
>> from
>> $200 through $FFFF as long.  Softswitches on $C000 through $CFFF will be
>> moved to higher RAM like $FF bank.  It has special switch to use
>> softswitches in $0/$1 bank for compatibility with Apple II.
>>
>>     We can change the 14M crystal oscilloscope chip to 28M crystal
>> oscilloscope.  We know that NTSC has 15.7K horizontal freq and 60Hz 
>> vertical
>> freq (262.5 * 60Hz).  We want 640x480 resolution.  We are going to have
>> 31.4K horizontal freq and 60Hz vertical freq.
>>
>>     28M crystal oscilloscope chip can cause 658C16 MPU to be 2 MHz and 
>> RAM
>> to be 4 MHz.  It is a problem.  I have a good understanding of timing
>> generator in HAL16R8 chip.  I should be able to modify timing generator 
>> to
>> run 1 MHz on 658C16 MPU and 2 MHz on RAM.
>>
>>     We need to have a good understanding how VGA monitor work first. 
>> What
>> do you suggest with my idea?
>>
>>
>> Bryan Parkoff
>>
>>
>
> Didn't they call it "The Apple //gs" a few years back? :)
Don,

    Apple IIgs is no good anymore unless VGA circuit is built in 
motherboard.  I do not support Second Sight card.  If you wish ti improve 
Apple IIgs, go to do it.  I call Apple IIegs.  It is enhanced Apple IIgs 
over existing Apple IIgs with ROM 01 and ROM 03.  It is like enhanced Apple 
//e over Apple II.

Bryan Parkoff