Measurement Computing ADAC-LVi User Manual

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Chapter 2 Digital I/O VIs

ADAC LabVIEW VI

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Data Transfer Method (Software:0) Data Transfer Method is a numeric value that sets
the hardware transfer method. This parameter specifies how data form the DIO is to be
transferred to buffers.

For DIO ports that do not support DMA or Interrupts Data Transfer Method must be set
to SOFTWARE. Only single read operations are available. The available options are:

0:SOFTWARE Data is transferred via a software controlled loop, supported by all DIO's.
1:DMA Data is transferred via DMA, supported by DIO's with DMA, capabilities.
2:IRQ Data is transferred via ISR, supported by DIO's with Interrupt, capabilities.

The default Data Transfer Method is 0:SOFTWARE.

Port Resolution (8 BIT:1) Port Resolution is a numeric value that whether the input or
output port is read or written in 4, 8 or 16 bit transfers. The available options are:
0:4 BIT
1:8 BIT
2:16 BIT

The default value is 1:8 BIT

Port Mask (b11111111) Port Mask is a binary value that selects the operation bits. All
bits set to one(1) in the Port Mask will acted upon during Interrupt or DMA transfers.
Port Mask is only configured when Data Transfer Method is set for DMA or Interrupt
acquisitions.

The default value is binary 11111111.

Number of Buffers(0) Specifies the number of buffers the VI allocates. Buffers are only
configured when Data Transfer Method is set for DMA or Interrupt acquisitions.

Buffer Size (1) Buffer Size is the number of data samples you each buffer to holds.
Buffer Size is only configured when Data Transfer Method is set for DMA or Interrupt
acquisitions.

error in (no error) Error in describes error conditions occurring before this VI executes.
This cluster defaults to no error.

Device Handle Device Handle is a numeric value that identifies the board's DIO
subsystem to be acted upon in subsequent VI subsystem calls.

error out Error out contains error information. If the error in cluster indicated an error,
the error out cluster contains the same information. Otherwise, error out describes the
error status of this VI.