"TC" <do-not-reply@i-do get-enough-spam-already-2498.com> wrote:
> BTW: my first computer was a VIC with a whole 5 kB main memory. To draw
> complex graphics (like a monochrome sine curve ;-) you had to fill the video
> memory with a sequence of ASCII chars, map the dot-matrix for those chars
> (8x16 dots) to memory, and then redefine the respective rectangular
> dot-matrices so that a graphical output would happen. If you have done this,
> everything windows throws at you is just a minor nuisance ;-)

Heh - the Amstrad CPC featured dedicated 16kB of pure-graphics display memory;
however, due to (mis-)using a display controller originally designed for text
operation, it wasn't too straightforward either:

- a raster line would be comprised of 80 bytes
- a batch of consecutive raster lines would have an address offset of 2048 to
each other
- each batch of lines would have an address offset of 80 bytes to one another

And if you forgot to clear the screen before directly accessing the display
memory, the start address might have been anywhere, due to the hardware
scrolling capabilities of the display controller...

(Double-buffering was nice though: The display controller could access any of
the four 16kB banks of RAM; bank 1 and 3 were of no use as the firmware used
parts for special purposes, but bank 4 was dedicated to the display, and with a
small enough program bank 2 could serve as a second frame buffer.)

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