2 off 28byj48 stepper motors with uln2003 boards

Hi, New to Arduino and just bought 2 new stepper motors with individual boards.


I am curious if there is a good approach to controlling 2 stepper motors concurrently. For example if sometimes I wanted both motors to start at the same time and both travel the same sweep at the same speed, but they are on separate boards? And at other times run one half the speed as the other. Any pointers or links on this topic for noobs like me would be appreciated.

It would be trivially easy to make them go the same speed. Just a couple lines of code. Not much harder to go half speed.