Re: Apple II VGA Video Generator Card Project

[bieling@terra.es (Jorge Chamorro Bieling)]

<aiiadict@gmail.com> wrote:

> >Think about how long it will take an Apple to fill a 1.2MB
> 
> Too long.
> 
> Even if the 6502 is running at 50mhz, imagine the nightmare
> of bankswitching out 64k chunks, then moving data from the
> active memory into the video buffer...
> 
> >There is a reason that higher resolutions
> >and color depths go with more powerful
> >processors (and with more RAM).
> 
> more powerful CPU = faster speed + more address lines. (and
> more linear addressable RAM)
> 
> We can put 16 megabytes of RAM in an apple II using
> AE bankswitch method (1 byte register selects which
> 64k block to present to the CPU.  256*64k= 16384k = 16megs)
> but what a pain it is to deal with this!
> 
> Rich

It's not if you just want to have 132 colums and 128 rows of text.
Or you just want to be able to hplot 0,0 to 1150,980.
Then it's a BIG pain when you have to deal with this as a bitmap...

That's why we have to think carefully about this things...
-- 
Jorge Chamorro Bieling