[A83] Re: greyscale


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[A83] Re: greyscale




At 20:46 2001-12-20, you wrote:
>It's different lcd drivers. We've talked about this before, but this is the
>basic idea:
>the 89 has a method that tells the driver that it is time to update
>on the 83, the driver is independent of the calc(and this varies depending on
>how new the batteries are).
>
>Thats why the 89 has 7 scale grey scale and we only have 2 colors :P

Yes.
But suckers idea is still right. On the 89 for 4 level gray you basicly 
have two buffers for the screen contents, and on an interrupt, you switch 
between the two. 2/3 of the time it displays one buffer, 1/3 of the time 
the other.
(there is other switching schemes but this is the most simple)
The 89 lcd driver has a port where you set from which adress in memory to 
read the screen contents.

///Olle






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