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Asked — Edited
Resolved Resolved by Rich!

Roli Forward And Backward Reverse

My friend just received new roli (I have one also). All work fine (servos, camera), except forward and backward movement are reversed. Checked h-bridge and ezb v4 wiring. Used ez robot cloud roli sample project. Tried on laptop and android phone. All same problem. Note that the right and left turning movement are ok.
Any idea ?


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United Kingdom
You could swap the forward and reverse ports with each other that your H-bridge motor controller is connected to in the "Movement panel" configuration screen in ARC.

So for example, if "Forward" is D3 and "Reverse" is D6, simply swap the D3 to D6 and D6 to D3. Hope this helps.:)
Recheck the wiring. Some Roli's had the hiring harness reversed (mine included) and that was the exact symptom.

@Steve G
I was thinking of doing that, but what do I do with the trigger A and B ports?
also roli will no longer be compatible with public project ?
United Kingdom
If you save the project as your own using "Save" or "Save as" you will be fine. Also, check out Alan's link. You might find this useful as well. I'm not at my computer right now, but a little easy trial and error swapping the trigger ports to see what controls what direction, should help you get your Roli doing what it should.
United Kingdom
Check the L298n H-Bridge tutorial I wrote a while back, it covers the common problems such as forward/backward reversed and left/right reversed.
Sorry all to get get back so late. I did find the problem and it was indeed a faulty wiring on the h-bridge. Thanks all, perticularly @Rich for your nice tutorial.