
Chapter 7 PC-TIO-10 Timing I/O Device
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National Instruments Corporation 7-5 DAQ Hardware Overview Guide
Programmable Frequency Output Operation
The Am9513-based devices have a 4-bit programmable frequency output
signal. This signal is a divided-down version of the selected timebase. You
can select any of five internal timebases, counter SOURCE inputs, and
counter GATE inputs as the FOUT source. See the
CTR_FOUT_Config
function in the NI-DAQ Function Reference Online Help or the
CTR_Control.vi in the LabVIEW DAQ Online Reference for FOUT use
and timing.
PC-TIO-10 Counter/Timers
The PC-TIO-10 contains two Advanced Micro Devices (AMD) Am9513
System Timing Controller (STC) chips, each of which provides five
independent 16-bit counter/timers and a 4-bit programmable frequency
output, FOUT. Each of the STCs is connected to an onboard 1 MHz
frequency source, thus giving internal frequencies as specified previously.
In addition, the SOURCE5 and SOURCE10 inputs are connected to
a 5 MHz frequency source that yields increased timing resolution.
All counter/timers are available for general-purpose counting functions.
All 10 counters and both FOUT outputs are connected to the I/O connector.
The GATE, SOURCE, and OUTPUT lines of each of the counters except
counters 5 and 10 are connected to the I/O connector. SOURCE5 and
SOURCE10 are used as additional frequency inputs; consequently, only the
GATE and OUTPUT lines of counters 5 and 10 are connected to the
I/O connector.
Some applications use two counters. Typically the two counters used are
adjacent counters. The PC-TIO-10 uses two AMD 9513 ICs. Counter 1
through 5 are in one IC and counters 6 through 10 are in the other IC.
Therefore, the upper adjacent counter for counter 5 is counter 1 not
counter 6. The entire sequence of adjacent counters is shown in Table 7-1.
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