I need to make a counter using either 74LS190 or 74LS191. It needs to count between 2 and 7, meaning from 2 up to 7 and then back down to 2. Ex: 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 3......
It has to be able to repeat this pattern 3 times and then stop.
This is a classwork assignment that I have been stuck on for about 2 weeks now.
Please help!!!!!!
thanks,
Julian

 

What have you tried?

Show your schematics, and what results you were getting.

 

Becides the 74LS191, are you allowed to use additional ICs?