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Asked — Edited

Roli H-Bridge Wired Backwards

After following the connection tutorial, my Roli was going backwards but turning in the right direction. After some tinkering and using the direction/correction charts in Rich's excellent l298n tutorial I determined that the wiring harness was connected backwards. Reversed the connection on all the wires except the powerband ground. So, to save other owners time figuring it out..... If you connect Roli following the tutorial and he goes bacwards, just flip the 6 pin cable around, hooking up the black wire to d0 and the green to d5 and all the others in order of the cable.

Alan


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Synthiam
#1  
I wonder if it's just yours or everyone's... Guess we will have to wait and see with others feedback.
#2  
I have the same issue. I just have not brought that one up yet.
#3  
I am okay. And I double checked my notes. And pictures I took and posted too.

j
#4  
What would be the best way to correct this issue? Pop open the body and change the polarity on the motor connections at the h-bridge?
#5  
I dont have one yet, but I think this is all that you would have to do (taken from above)

If you connect Roli following the tutorial and he goes bacwards, just flip the 6 pin cable around, hooking up the black wire to d0 and the green to d5 and all the others in order of the cable.

This is normal, so
D0 - Green (Left PWM)
D1 - Blue (Left Trigger A)
D2 - Purple (Left Trigger B)
D3 - Grey (Right Trigger A)
D4 - White (Right Trigger B)
D5 - Black (Right PWM)

Yours would be
D0 - Black
D1 - White
D2 - Grey
D3 - Purple
D4 - Blue
D5 - Green
United Kingdom
#6  
The "best" way will vary depending on how you define best.

Correcting the polarity of the motors which are running incorrectly is, in my opinion the best way but this isn't the easiest or quickest way.

It can be corrected in the H-Bridge control panel config, with adjusting the In1 to In4 of the H-Bridge or by changing which ports connect to which In1 to In4 at the EZ-B end.

Config option is going to be quickest but will need adjusting after any Example Project updates by EZ-Robot.

Plenty of options, choose whichever seems easiest for you.

P.S. Glad my tutorial/write up helped:)
#7  
Thanks guys. I guess I was asking for the "recommended" fix from EZ-Robot. I have not popped open the body to check to see if it was wired backwards at the h-bridge, which is what I suspect. I know it would be easier to just swap the wires at the pins, but I would rather not wire it differently there than what the tutorials instruct. It's not a big deal either way. I'll get it straightened out.
#8  
The advantage of flipping the cable around (and using the Tutorial to figure out what was going on) what that I didn't need to open up Roli to see/modify the connections on the H-bridge. Once I determined that the PWM controls where also backwards, it was a simple fix to just reverse the cable.

Thanks d.cochran for spelling out exactly what I meant. I was typing from my phone, so tried to make the post as simple as I could but still enough information to help anyone who was stuck.

Alan
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