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I forgot about that ”scrolling algorithm” that the teletext has. It instantly feels familiar but I wonder how its actually implement.

You input a page number and it seems to pick the right spot on the hundreds place, and then seems to arbitrarily drop into a loop for the right page number. Doesnt seem to have any logic, as if a spinner with the numbers 01-99 is constantly whirring in the background




The page data is transmitted every blanking interval. The most frequently-accessed pages are transmitted most frequently, and the infrequently-accessed pages are transmitted least frequently (so you have to wait longer for them to come up).


But if your TV was expensive enough it had a bit of RAM that stored the pages as they were broadcast, so keying in the number took you straight there.




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