National Instruments 653X Manuale Utente

© National Instruments Corporation

To monitor your data transfer once data transfer starts:

•

NI-DAQ C interface—Call 

DIG_Block_Check

 to monitor finite data 

transfer. For continuous transfers, use 

Get_DAQ_Device_Info 

to 

obtain the cumulative transfer count (

DIG_Block_Check 

does not 

return the number of buffer iterations completed). The following table 
lists the attribute types and values returned for 

Get_DAQ_Device_Info

:

You should always read the least significant bits of the transfer count before reading 

the most significant bits. The 32 most significant bits of the transfer count is cached in 
software when you read the least significant bits.

•

LabVIEW—Use the Digital Buffer Write VI or the Digital Buffer 
Read VI, which are called by the DIO Read VI, the DIO Write VI, and 
the DIO Wait VI.

Connect digital input signals to the I/O connector using the pinout 
diagrams, Figures C-1, 

, or C-2, 

.

If you are using an external source for your REQ signal, connect it to the 
appropriate REQ pin of the I/O connector. 

Input

ND_READ_MARK_H_SNAPSHOT_GR1

Most significant 32-bit of transfer count

ND_READ_MARK_H_SNAPSHOT_GR1

ND_READ_MARK_L_SNAPSHOT_GR1

Least significant 32-bit of transfer count

ND_READ_MARK_L_SNAPSHOT_GR2

Output

ND_WRITE_MARK_H_SNAPSHOT_GR1

Most significant 32-bit of transfer count

ND_WRITE_MARK_H_SNAPSHOT_GR2

ND_WRITE_MARK_L_SNAPSHOT_GR1

Least significant 32-bit of transfer count

ND_WRITE_MARK_L_SNAPSHOT_GR2