Hi,

Could I ask you not to have the text sliding in 1 column at a time? *I* get sea-sick, watching this kind of display! Why not bump in 1 word at a time, or better, fill up the display with a series of words & hold for a couple of seconds. Most normal people can read that fast!
If you intend to use a matrix of LEDs, remember it gives less flicker if you update a complete row of dots in 1 go, instead of a complete column. I've done this for a factory security synoptic panel (door & sprinkler contacts, etc). The guy I took the project over from was running the 30x8 LEDS by scanning the columns (only 3% duty cycle!). I re-wrote the driver to "broadside" the display, boosting the duty cycle to 12% - better visibilty, & no flicker!
Oh yes, & it was an 8085.

Good luck,

Richard