Quote Originally Posted by daverob View Post
You don't need to connect the 'clear' (clr) pin as all it does is blank the displays, and you can achieve this by writing to both of them.
Thats good to know, I wasn't sure that if it got the next clock impulse with no D inputs what would happen,

I will try to make a list of all the inputs and outputs needed, to get to the next step forward. Although reading online forums, a scrolling display would require a lot of similar coded lines. But once its started, just copy and paste and alter the output config.