Appendix C
Common Questions
C-4
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National Instruments Corporation
up/down control, single or pulse train generation, equivalent time
sampling, buffered period, and buffered semiperiod measurement.
What is the difference in timebases between the Am9513
counter/timer and the DAQ-STC?
The DAQ-STC-based MIO boards have a 20 MHz timebase. The
Am9513-based MIO boards have a 1 MHz or 5 MHz timebase.
Will the counter/timer applications that I wrote previously, work
with the DAQ-STC?
If you are using NI-DAQ with LabVIEW, some of your applications
drawn using the CTR VIs will still run. However, there are many
differences in the counters between the 611X E and other boards; the
counter numbers are different, timebase selections are different, and the
DAQ-STC counters are 24-bit counters (unlike the 16-bit counters on
boards without the DAQ-STC).
If you are using the NI-DAQ language interface or LabWindows/CVI,
the answer is no, the counter/timer applications that you wrote
previously will not work with the DAQ-STC. You must use the GPCTR
functions; ICTR and CTR functions will not work with the DAQ-STC.
The GPCTR functions have the same capabilities as the ICTR and CTR
functions, plus more, but you must rewrite the application with the
GPCTR function calls.
I’m using one of the general-purpose counter/timers on my
611X E board, but I do not see the counter/timer output on the I/O
connector. What am I doing wrong?
If you are using the NI-DAQ language interface or LabWindows/CVI,
you must configure the output line to output the signal to the I/O
connector. Use the
Select_Signal
call in NI-DAQ to configure the
output line. By default, all timing I/O lines except EXTSTROBE* are
tri-stated.
What are the PFIs and how do I configure these lines?
PFIs are Programmable Function Inputs. These lines serve as
connections to virtually all internal timing signals.
If you are using the NI-DAQ language interface or LabWindows/CVI,
use the
Select_Signal
function to route internal signals to the I/O
PCI_E.book Page 4 Thursday, June 25, 1998 12:55 PM