Need some last-minute conversion support, please. The team has switched its wrist encoder to the REV through-bore hex encoder with 6pin cable attached directly to a Sparkmax. We are controlling a brushed HDHex Rev motor. Programming says they can find it and keep getting a sensor fault. Cables tested for continuity and swapped out. Multiple sparks swapped out. Encoder was swapped out. So I am wondering how this may be misconfigured in our understanding of the control pathway between all three. Any help will let us get back to driving practice for districts- Thank you so much.
Reference: REV support guide:
Make sure you configure the spark max to brushed mode and change the sensor type. May need to clear faults to make sure it is all working. And dont for get to burn flash.
but it is a CIM…it is brushed. NEOs…sure. Check for sticky faults.
Also, does that sensor work with a CIM? NEOs…sure. Not sure about CIMs…
Apparently this particular picture comes from REV’s own support guide. Therefore, it does work. REV isn’t in the habit of putting non-working stuff in their guides.
Brushed motor in a Spark Max: Make sure the Spark is in Brushed mode, leave the white wire disconnected when you connect the red and black wires.
If the sensor works with a Spark Max, it’ll work. NEO encoders are internal, CIMs don’t have their own internal so rely on through-bore and other encoders–which in this case are routed into the Spark Max. HDHex motors have internal encoders but those can work with a SparkMax.
On to the setup at hand.
First question: Has the onboard sensor for the HDHex been disconnected?
Second question: Does the Spark Max know that said sensor is disconnected?
Third question: Is anything else connected to the motor or speed controller?
4th question: What do you mean by “Programming says they can find it and keep getting a sensor fault”?
You’ve swapped all the hardware and still have the issue. That leaves 2 options: 1, you have something that’s corrupting hardware. Possible, but unlikely. 2, your configuration is bad and your hardware is good. So, go through the programming setup that was previously posted. Set the motor to the right motor, the controller to the right type, and the sensor to the proper sensor. If it still doesn’t work, I’m out of ideas* but I’m sure someone else will have some.
*Other than, “are you sure that motor is strong enough?”, but given that you’ve made it through two events and haven’t changed it I’m going to assume that it is.
IF it was connected with Wago’s…was a pull test done?
We had a CIMs SparkMax combo for drivetrain. had some severe drifting during auto…and our driver was fighting it during teleop. Morning of day two…swapped the “problem” CIM…issue continued in the first match of the day. Coder checked the SparkMax…that was the problem.
Another thing that MAY be a problem is IF you are using Wago’s…do a gentle pull test…IF you hadn’t. We ran into that as well. IF it is disconnected, reseat, clear faults.
One thing is that we wanted to use it as an absolute encoder. In the end, we created a breakout board wired with only three of the 6 pin wires connected, 2 power and a signal, and used the spark data port on the top to connect it. NOt confirmed yet that it is working as absolute encoder, but am sure its running and being seen by programmers now. WE never got the REV method of direct connection working. THnak you both for your help. Luckily no WAGOs were involved. Dont allow them on competition bot.
In the end, we managed to hot wire a REV data port connection to connect the encoder to the sparkmax. It was not possible to control the brushed motor directly through the encoder plugged directly into the spark. REV does have a data port interface as well that we became aware of later on, but did not use it yet.
CG
The through bore encoder is just a quadrature/absolute encoder. The Spark Max’s JST port and 10-pin port share encoder pins, hence the need for Alternate Encoder Mode when using a brushless motor.
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