Le 26/10/2015 23:43, Orchid Win7 v1 a écrit :
> I've always wanted to know... why is the framebuffer arranged so
> weirdly? Like, as you load a picture file, rather than filling from top
> to bottom, it seems to fill every Nth line...

Probably because Pal is an interleaved image: there is odd and even 
frames. It was probably easier for the electronic in charge of 
generating the lines in that order instead of obvious linear order.

IIRC the memory was not a dual access memory (that's expensive), so for 
the chip to generate the signal, it might have been easier to read 
consecutive address (an hardware counter is cheap).

Oh, it was a time in which accessing memory was easy: presents an 
address on the address bus, read the data on the data bus. No column & 
no row selection, no wasted cycles to wait for the data (no CAS Latency !)

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