RE: DRV8880: Behavior of changing the step during motor operation

Hi Shimizu-san,

For this discussion, we will assume each step will move cause the step number to increase.

"Maybe, when customer changes from 1/4 step to 1/16 step, step is changed from 2 to 5.

and when customer changes from 1/16 step to 1/4 step, step is changed from 5 to 2.
I show this below.
Is this correct?"

You can think of the step changing as you described above. The current is the same in the example, so there is no difference between step 2 in 1/4 and step 5 in 1/16.
In reality, the new step mode is entered when the next step command is received.


"But I don't know that when customer changes from step6 of 1/16 to 1/4 step.
At which step does DRV8880 indexer operate?"

As mentioned above, the step does not change when the microstep mode changes. The step changes when the step command is received.
So in the example:
The indexer is at step 6 in 1/16 mode (electrical angle 28.125 degrees)
The step mode is changed to 1/4
The indexer remains at step 6 in 1/16 mode (electrical angle 28.125 degrees)
A step input is received
The indexer changes to step 3 of 1/4 mode ( (electrical angle 45 degrees)