From: kegs@provalid.com
In article ,
D Finnigan wrote:
>Kent Dickey wrote:
>> In article ,
>> D Finnigan wrote:
[snip]
>>>In previous Apple II designs, the reÂfreshing of memory was tied directly
>>>to
>>>the Apple II video mode. The Mega II includes an 8-bit counter for
>>>refreshÂing the 128K bytes of (slow) memory associated with the Apple
>>>IIe/IIc model; it does five cycles of RAM refresh during the horizontal
>>>retrace of each video scan line and refreshes the 128K bytes of memory in
>>>3.25 milliseconds. By taking care of RAM refresh the Mega II chip opens
>>>the
>>>Apple II design to new video modes that were impossible before.
>>
>> I don't know the source of the above paragraph and what it's trying to
>> say,
>> but I do not believe it is correct.
>
>The source is the October 1986 BYTE Magazine article by Gregg Williams,
>senior technical editor at BYTE.
>
>It's on page 86 of the issue of BYTE magazine dated October 1986.
>
>
>--
>]DF$
>The New Apple II User's Guide:
>https://macgui.com/newa2guide/
Sorry, I didn't mean to imply I doubted that BYTE magazine published those
statements in 1986. I meant I'm not sure what his source was, but I believe
he is mistaken. He seems to have fumbled up the SHR being able to read
the SCB (one cycle) and palette data (read in 4 cycles) during HBL with a
change to how refresh works.
Kent
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