Spark MAX and External Encoder Max Speeds

Hey guys. We plan on regulating our shooter velocities this year with encoders , either the VersaPlanetary integrated CRTE Mag Encoder or the REV Through The Bore Encoder, with RS775 Pros. What I would like to do is connect the encoder to a SparkMax through the Data or Encoder Port (MAG encoder or Through the Bore respectively) and use closed-loop PID to adjust and maintain a certain velocity, however, it is very likely that the RPM of the shooter will exceed the max RPM for either encoder according to REV’s website.

Has anyone tried to run closed-loop PID on the Maxes with high speeds such as a shooter? Did it work in reality or not? Or should I just give up on reading it with the SparkMaxes and just wire it to the Rio? Just looking to see if someone has tested high speed encoder readings already and see if it is a plausible idea.

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Are you running a Neo? It has an internal encoder.

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You could also use an encoder with fewer tics per revolution. If you’re spinning that fast, you can still get pretty good resolution on your speed with only a few cycles per revolution.

For higher speeds/controlling velocity:

  • If you are driving a NEO use the built-in encoder.

  • If you are driving a brushed motor, use the encoder port, or the roboRIO which do not have the same limitation.

Do not exceed the spec for the alternate encoder port.

I’m not using a neo with the Max. I plan on using a RS775 Pro. We don’t have any Talon SRX’s but we have a couple Spark MAX’s. So, to clarify, if I were to plug a Rev Through The Bore Encoder into the encoder port on the max, it will be able to read a greater RPM? Or is it the same limitation? Because if it is the same limitation, I’ll just use the RoboRIO to read the encoder. The max speed will be closer to 6000 RPM which is juuuuust a tad too high.

You can use either option.

What is the spec for the encoder port? I don’t see that in the user manual.

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