Read Breakpoint StatusReads the breakpoint status for all axes or encoders.
| Device Compatibility
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Breakpoint Type (Position) is a reserved input that must be set to Position Breakpoint (0). | |||||||||||||||||||
Board ID is a unique number assigned by Measurement & Automation Explorer (MAX) used to send and receive commands and data to or from a specific NI motion controller. | |||||||||||||||||||
Axis or Encoder is the axis control or encoder control selector. For multi-axis status, use 0 (zero). For multi-encoder status, use 0x20. | |||||||||||||||||||
Ret Vect indicates the destination for the return data generated by this VI. Available return vectors include return data to the host (0xFF), return data to a variable (0x01 through 0x78), return data to an indirect variable (0x81 through 0xF8), and do not return data (0). Refer to Input and Return Vectors for more detailed information. | |||||||||||||||||||
error in (no error) describes error conditions that occur before this VI runs. The default input of this cluster is no error. If an error already occurred, this VI returns the value of error in in error out. The VI runs normally only if no incoming error exists. Otherwise, the VI passes the error in value to error out. The error in cluster contains the following parameters:
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Breakpoint Status
is the bitmap of breakpoint status for all axes or all encoders.
When reading breakpoint status for axes (Axis or Encoder = 0) or encoders (Axis or Encoder = 0x20):
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Bd ID Out is provided for flow control. You can string together NI-Motion VIs by wiring the Bd ID Out terminal of one VI to the Board ID terminal of the next VI. | |||||||||||||||||||
Resource Output is the Axis, Vector Space, ADC, or Encoder you wired into the VI. Use Resource Output to pass the resource to another VI and/or to display information about the device. | |||||||||||||||||||
error out contains error information. If error in indicates an error, error out contains the same error information. Otherwise, it describes the error status that this VI produces.
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Using This VI
This VI allows you to see if a breakpoint has occurred or is pending. When you enable a breakpoint, the corresponding status bit is reset to indicate that the breakpoint is pending. For single breakpoints, this status is set when a breakpoint occurs. Periodic breakpoints only set the breakpoint status after the first breakpoint has occurred, and the status remains asserted across the subsequent breakpoints. When the breakpoint position is reached, its status bit is set to True (1).
Example
Executing the Read Breakpoint Status VI with Axis or Encoder = 0x20 and Breakpoint Type = 0 returns Breakpoint Status, which corresponds to the following bitmap.
Axis/ Encoder 1 |
Axis/ Encoder 2 |
Axis/ Encoder 3 |
Axis/ Encoder 4 |
Axis/ Encoder 5 |
Axis/ Encoder 6 |
Axis/ Encoder 7 |
Axis/ Encoder 8 |
True | False | False | True | False | False | False | False |
On encoders 1 and 4, breakpoints have occurred, but on encoders 2 and 3, breakpoints are pending or were never enabled.
Note Read Breakpoints Status returns the breakpoint status for either all axes or all encoders, based on which value is passed into Axis or Encoder. |