flex_read_velocity_rtn

Device Compatibility Device Compatibility 7330 Y 7340 Y 7344 Y 7350 Y 7390 Y NI SoftMotion Controller for CANopen—Xenus Y NI SoftMotion Controller for CANopen—Accelnet Y

Read Velocity Return

Usage

status = flex_read_velocity_rtn(u8 boardID, u8 axisOrVectorSpace, i32* velocity);

Purpose

Reads the filtered velocity of an axis or vector space.

Parameters

Name	Type	Description
boardID	u8	assigned by Measurement & Automation Explorer (MAX)
axisOrVectorSpace	u8	axis or vector space to read
velocity	i32*	axis or vector space filtered velocity in counts/s (servo) or steps/s (stepper)

Parameter Discussion

axisOrVectorSpace is the axis or vector space to read. Valid values are NIMC_AXIS1 through NIMC_AXIS30 or NIMC_VECTOR_SPACE1 through NIMC_VECTOR_SPACE15. On motion controllers that support fewer than thirty axes, reading non-existent axes or vector spaces returns error –70006 (NIMC_badResourceIDOrAxisError). Refer to Axes and Vector Spaces for axis and vector space resource IDs.

velocity is filtered velocity in counts/s (for servo axes) or steps/s (for stepper axes). The sign of velocity indicates direction of motion. For vector spaces, velocity is the filtered vector velocity for the vector move.

Using This Function

This function returns the axis or vector space filtered velocity. To reduce the effects of noise and jitter on the filter calculation, the data this function returns is averaged based on parameters set in the Load Velocity Filter Parameter function.

For vector spaces, this function returns vector velocity, the root-mean-square of the filtered velocities of the individual axes that make up the vector space.

Note  You also can read velocity in RPM by calling the Read Velocity in RPM function.

Note  Refer to Function Execution Times for benchmark timing information about your controller.