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gmueckl 2 hours ago

No, this is technically not fully correct. Early text based display output systems were relying on special character generator hardware to generate the display signals producing the text on screen. Those systems did not have any means of generating arbitrary pixel patterns.

weinzierl an hour ago | parent [-]

Do you have an example? All the 8-bitters I know drew the characters from memory, which was a character ROM per default but could be changed either with a screw driver or by bank switching some RAM in-place.

EDIT: If you mean they were not copied in a frame buffer first, you are right. I should not have written 'blitting'.

awkwardleon an hour ago | parent | next [-]

Maybe too old to be applicable here, but the TRS-80 Models I and III (and probably more models) had no way to address pixels. You had to use semigraphic characters to emulate larger blocks at sub-character resolutions. https://bumbershootsoft.wordpress.com/2022/01/28/touring-the...

adiabatichottub 21 minutes ago | parent | prev | next [-]

I recommend reading the TV Typewriter Cookbook.

https://archive.org/details/tvtcb_doc

direwolf20 an hour ago | parent | prev | next [-]

With character RAM you can still only have up to 256 unique 8x8 blocks on screen.

LoganDark an hour ago | parent | prev [-]

The character ROM was not read and processed by the CPU. The CPU set some bytes in video RAM, which served as indexes into the character ROM by the video output hardware.

I believe on some systems there were some tricks that allowed some bitmap display by redefining glyphs. One example off the top of my head is The 8-Bit Guy's Planet X2, which can use text mode but with glyphs redefined to use for icons, units, terrain, UI, etc.