User manual

Chapter 3 Software Overview
NI-DAQ User Manual for PC Compatibles 3-106 ni.com
REQ1 and REQ2 are request signals generated internally or received from
the I/O connector. ACK1 and ACK2 are acknowledge signals used for
handshaking mode; in pattern-generation mode, they can carry start trigger
signals instead. PCLK1 and PCLK2 are the peripheral clock lines for burst
mode. STOPTRIG1 and STOPTRIG2 are used for data acquisition timing.
For more information about the 653X signals, refer to the DIO 653XUser
Manual. Find additional explanations of the ACK1, ACK2, STOPTRIG1,
and STOPTRIG2 signals in the
DIG_Trigger_Config
function in the
NI-DAQ Function Reference Online Help file.
RTSI Bus Application Tips
This section gives a basic explanation of how to construct an application
that uses RTSI bus NI-DAQ functions. Use the flowcharts as a quick
reference for constructing potential applications from the NI-DAQ function
calls.
An application that uses the RTSI bus has three basic steps:
1. Connect the signals from the device to the RTSI bus.
2. Execute the work of the application.
3. Disconnect the signals from the RTSI bus. Figure 3-40 illustrates
the normal order of RTSI function calls.
Figure 3-40. Basic RTSI Application Calls
Connect clock signals on RTSI bus?
RTSI_Clock
RTSI_Conn
Disconnect all device
and clock signals
from RTSI bus.
RTSI_Clear
Disconnect device signal
from RTSI bus.
Disconnect clock signal
from RTSI bus.
RTSI_DisConn
RTSI_Clock
Connect each device signal to a specified
RTSI bus trigger line. A completed signal path
requires two
RTSI_Conn calls.