First, let me warn you that the current snapshot is not functional for the closed loop modes. If you check out the latest SVN code, then things should work for you. I fixed some bugs in the last few days so make sure you are up to date.
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Originally Posted by Andy Bradley
For starters, what are the differences in the control modes for the open vi: Percent Vbus, Speed, Position, and current - and how do they relate to the status info that can be read back?
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The Percent Vbus is the same open loop mode that you get with PWM... it's just higher resolution than the PWM interface. Speed mode uses an encoder as a reference sensor to attempt to maintain a speed you set in spite of load or voltage changes. Position is the same, except that instead of a fixed speed, it uses a fixed position and can use a single- or multi-turn potentiometer or an encoder as a reference. Current mode attempts to drive the motor as a fixed current (which is related to torque) in spite of variable load. They are pretty much independent of the status data.
Quote:
Originally Posted by Andy Bradley
Also, can I use the jaguar as a connection point for an encoder without using the sensor to control that particular motor?
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You could, but I wouldn't recommend it since it is slower to read from the Jag than directly from the cRIO's 9403. If you do this, you won't have any feedback for the motor you are actually controlling so you would need to be in open-loop Percent Vbus mode.
Quote:
Originally Posted by Andy Bradley
Finally, if a potentiometer or encoder is connected to the jaguar, what is displayed for the status->speed value? Counts per sec? degrees?
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The output is in RPM assuming you configured the number of lines in your encoder. The potentiometer is not a valid speed reference.
If you read the position status, then it is based on the position reference that you select (encoder or pot) and the output is the number of rotations.
-Joe