Acquiring Data Using Two E Series Devices Connected by RTSI and a Shared Scan Clock

This VI acquires data into separate single buffers from two E Series devices (or devices with similar timing/triggering signals) simultaneously by sharing the scan clock (AI scan start). The master device, which uses an internal clock and start trigger, sends its AI scan clock signal over the RTSI bus. The slave device receives it to time its acquisition.
To expand this example to use more than two devices, replicate the sequence of VIs called for the slave device. Note that a single error cluster is chained.
NOTE: You must use NI-DAQ version 6.1 or later for this example.

INSTRUCTIONS:
1. Enter the master and slave device numbers. Make sure they are different device numbers, and that they are valid DAQ devices.
2. Enter the channels on which you want to acquire data.
3. Modify the number of scans to acquire and master scan clock rate, if desired.
4. Connect your analog input signals to the two devices, as described below in the I/O CONNECTIONS section.
5. Run the VI.

KEY PARAMETERS:
Route Signal.vi (master device):
signal name = RTSI0(12), signal source = AI scan start(9)

AI Clock Config.vi (slave device):
which clock=scan clock(1), clock source=RTSI high-low; "0"

AI Control.vi (slave device):
to avoid reconfiguring the scan clock, control code = START

Route Signal.vi (master device - to disconnect):
signal name = RTSI0(12), signal source = none(1)

I/O CONNECTIONS:
Connect your analog input signals to the channels on the I/O connector for your device to match the channels you have chosen on the front panel of this VI.
For actual pin names, refer to your hardware user manual.
NOTE: If you do not have the proper RTSI connections between your devices, you will get a timeoutError (-10800) on the slave device. (This note does NOT apply to PXI devices.)

DAQ VIs USED:
AI Config.vi
AI Clock Config.vi
Route Signal.vi
AI Start.vi
AI Control.vi
AI Read.vi
AI Clear.vi

Requirements

Filename: two_e-series_shared_scanclk.zip

Software Requirements

Application Software: LabVIEW Full Development System 5.0.1
Language(s): LabVIEW

Hardware Requirements

Hardware Group: Multifunction DAQ (MIO)
Driver: Traditional NI-DAQ (Legacy)

Reader Comments | Submit a comment »

Not as fast as shared channel clock as described in "synchronizing analog input by sharing channel clock on RTSI".
- Jian WEI, Rutgers University. weijian@physics.rutgers.edu - Jun 6, 2003