Справочник Пользователя для National Instruments Welding System 321645c-01

Chapter 2

Function Reference — GPCTR_Watch

NI-DAQ FRM for PC Compatibles

2-246

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 National Instruments Corporation

ND_COUNT

This is the counter contents. entityValue can be between 0 and 2

24

 – 1 for E Series and 445X 

and between 0 and 2

32 

– 1 for 6602 and 455X devices.

ND_COUNT_AVAILABLE

If the application is 

ND_TRIG_PULSE_WIDTH_MSR

, 

ND_SINGLE_PULSE_WIDTH_MSR

, or 

ND_SINGLE_PERIOD_MSR

, this entityID allows you to see whether your measurement has 

completed. 

Corresponding entityValue indicates the following: 

ND_YES

—the measurement has 

completed; 

ND_NO

—the measurement has not completed.

ND_AVAILABLE_POINTS

If the application is buffered event counting or time measurement, this entityID allows you 
to see how many points have been transferred to the buffer.

ND_ARMED

Indicates whether the counter is armed. entityValue can be 

ND_YES

 or 

ND_NO

. You can use 

this in applications such as 

ND_SINGLE_PULSE_WIDTH_MSR

 for finding out when the pulse 

width measurement completes.

ND_TC_REACHED

Indicates whether the counter has reached terminal count entityValue can be 

ND_YES

 or 

ND_NO

. You can use this in applications such as 

ND_SINGLE_PULSE_WIDTH_MSR

 for 

detecting overflow (pulse was too long to be measured using the selected timebase).

ND_DONE

When the application is 

ND_SINGLE_TRIG_PULSE_GNR

, this indicates that the pulse has 

completed. entityValue can be 

ND_YES

 or 

ND_NO

. When the application is 

ND_RETRIG_PULSE_GNR

, this indicates that an individual pulse has completed. In this case, 

the indication that an individual pulse has completed will be returned only once per pulse by 
the 

GPCTR_Watch

 function.

ND_OUTPUT_STATE

You can use this to read the value of the counter output; the range is 

ND_LOW

 and 

ND_HIGH

.

ND_READ_MARK

 (6602 and 455X devices only)

Indicates the read mark in the buffer when a double-buffer operation is in progress. 
entityValue can be between 0 and 2

32

 – 1.

entityID = 

ND_WRITE_MARK

 (6602 and 455X devices only)

Indicates the location in the buffer (specified in 

GPCTR_Config_Buffer

) in which the latest 

input data has been written. entityValue can be between 0 and 2

32

 – 1. 

entityID = 

ND_INTERNAL_MAX_TIMEBASE

 (6602 and 455X devices only)

Indicates the maximum frequency of the timebase available for a counter. The entityValue is 
in Hertz.