Transferring Data Between Two Devices-Handshaking I/O; Choosing The Width Of Data To Transfer; Deciding Data Transfer Direction; Deciding Which Handshaking Protocol To Use - National Instruments 653 Series User Manual

Because output data is preloaded to the NI 6534 buffer, you cannot use DAQEvents
Note
(called Progress events in the CWDO object of Measurement Studio) to monitor the
progress of pattern generation. A DAQEvent is fired when data is preloaded into the
NI 6534 onboard memory from the PC memory, so the event indicates a data transfer from
the PC memory, not the progress of pattern generation from the NI 6534 to an external
device.
Transferring Data Between Two
Devices—Handshaking I/O

Choosing the Width of Data to Transfer

Deciding Data Transfer Direction

Deciding Which Handshaking Protocol to Use

© National Instruments Corporation
If you want to communicate with an external device using an exchange of
signals to request and acknowledge each data transfer, use the handshaking
I/O mode.
You can choose between a width of 8, 16, or 32 bits. Use the following
table to find the valid combinations of ports and timing controllers you can
use based on the width of data you want to transfer.
Table 2-3. Port and Timing Controller Combinations
Transfer
Width
8 bits Port 0 (DIOA<0..7>)
Port 2 (DIOC<0..7>)
16 bits Port 0, Port 1
Port 2, Port 3
32 bits Port 0, Port 1, Port 2, Port 3
You can choose to send data from the NI 653X to the peripheral device
(output) or from the peripheral device to the NI 653X (input).
The NI 653X supports several different handshaking protocols to
communicate with your peripheral device. The protocol you select
determines the timing of the ACK and REQ signals.
Possible Port
Combinations
2-17
Chapter 2 Using Your NI 653X
Timing Controllers
That Can Be Used
Group 1
Group 2
Group 1
Group 2
Group 1
NI 653X User Manual