Tabor Electronics 5251, Руководство пользователя

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TE5251
User Manual
4-78
Counter/Timer
Programming
Use the following command for programming the counter/timer
measuring function and other parameters. The counter/timer
function is created digitally however, it closely simulates a stand-
alone counter/timer so its functions are programmed just as they
would be programmed on a dedicated instrument. The
specifications and limitations of the counter/timer are specified in
Appendix A.
COUNter:FUNCtion{FREQuency|PERiod|APERiod|PULSe|ITOTalize|
GTOTalize(?)
Description
This command will program the measurement function for the counter/timer. Each measurement can be set
up with its gate time (where applicable) and display mode.
Parameters
Name Type Default Description
FREQuency Discrete FREQ Will select the frequency measurement function.
Frequency is measured on continuous signal only. The
result of the frequency measurement has gate-dependent
resolution. The 5251 displays 7 digits of frequency
reading in one second of gate time. If the gate time is
decreased, the number of displayed digits decreases
proportionally to the gate time interval. Reduce the gate
time when you want to accelerate the reading process
however, always make sure that the period of the signal
is smaller than the gate time setting.
PERiod Discrete Will select the period measurement function. Period can
be measured on either continuous or non-repetitive
signals. Since the period of the signal is directly
proportional to the gating time, the number of displayed
digits decreases proportionally to the period of the signal.
If you need to have more resolution and you signal is
repetitive, use the period averaged measurement
function. The best resolution in period measurements is
100 ns.
APERiod Discrete Will select the period averaged measurement function.
Period averaged can be measured continuous signals
only. In fact, this is the inverse function of frequency and
therefore, gate time determines the resolution of the
reading. Reduce the gate time when you want to
accelerate the reading process however, always make
sure that the period of the signal is smaller than the gate
time setting.
PULSe Discrete Will select the pulse width measurement function. Pulse
width can be measured on either continuous or non-
repetitive signals. Since the width of the signal is directly