Use more than 12 servos on UNO, but only 12 simultaneously?

Projects Programming
1

Hi, trying to learn fast... Using an Uno to control 6 legged robot with 12 servos. Walks fine, problem is we want to operate 2 more servos when the robot stops walking. I know the answer would be to switch to the Mega but robot already built and wanted to stick with the Uno.

My question is... Is it possible to detach the 12 servos used for walking, attach the 2 extra servos temporarily then detach those and re-attach the 12 to continue walking?

Also should I be avoiding digital Pins 0 and 13 in my testing? these happen to be where the 2 extra servos currently are?

Cheers!

2

The limit on the number of servos is present because a timer can only control so many servos, and there are only so many timers.

If you detach the servos associated with a given timer, you can then use that timer to control other servos.

The trick is knowing which timer controls which servo, so that you detach the proper servos.

When you detach a servo, it will not hold its position, so detaching any servo used to hold a pose is not a good idea.

It is a good idea to not use pins 0 and 1, so that you can use them for debugging.

The analog pins can be used for controlling servos.

I know the answer would be to switch to the Mega but robot already built and wanted to stick with the Uno.

If size is the issue, there are Mega clones that are the same size as the Uno.

3

Thanks PaulS, going to try to reallocate the timer and see what effect it has on the positions on re-attach. If I centre the servos immediately after, my idea is that it won't really notice or be important.