At VDS, there was 68000-based titler called Vidstar or Videostar, something like that. This was before the great DRAM price decline, so every effort was made t

At VDS, there was 68000-based titler called Vidstar or Videostar, something like that. This was before the great DRAM price decline, so every effort was made to reduce the memory including the frame buffer. (on previous products they experimented with bubble memory and even shipped a product using CCD memory). So the frame buffer was compressed using run-length coding. The hardware decoded it on the fly when generating the video. Anyway, we could get very high resolution this way with a tiny fast SRAM frame buffer, it looked great. A problem was that even with the 68000, composing a page from text was quite slow: 10 seconds for single line, something like that. One of the products was a teleprompter. To make smooth slow scrolling without complex sampling we moved the screen by changing the vertical sync position. This is not so easy to do well because the vertical sync detector in the monitor is pre-charged by the nearest horz sync (this is why NTSC has the double-rate serration pulses for interlace). On the other hand, we did roll and crawl effects using fast 6809 assembly on other products. The font on this type was very crude- either fixed width characters like a terminal or semi-proportional spaced, where the width had to be a multiple of some number of pixels (so still character cells). You could get away with it on CATV bulletin board devices, but not in high quality titlers.