Agilent Technologies Infiniium 90000 Q-Series, Руководство программиста

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700 Agilent Infiniium 90000 Series Oscilloscopes Programmer's Reference
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Pod Commands
:POD<N>:THReshold
Command
:POD<N>:THReshold {CMOS50 | CMOS33 | CMOS25 | ECL | PECL | TTL
| DIFFerential | <value>}
The :POD<N>:THReshold command sets the logic threshold value for a pod.
Pod 1 has the digital channels 0 through 7, and pod 2 has the digital
channels 8 through 15. This command is equivalent to the
:DIGital<N>:THReshold command.
The threshold is used for triggering purposes and for displaying the digital
data as high (above the threshold) or low (below the threshold). The
voltage values for the predefined thresholds are:
• CMOS50 = 2.5 V
• CMOS33 = 1.65 V
• CMOS25 = 1.25 V
• ECL = - 1.3 V
• PECL = 3.7 V
• TTL = 1.4 V
• DIFFerential = 0 V
<N>
An integer, 1- 2.
<value> A real number representing the voltage value which distinguishes a 1 logic
level from a 0 logic level. Waveform voltages greater than the threshold are
1 logic levels while waveform voltages less than the threshold are 0 logic
levels.
The range of the threshold voltage is from - 3.75 volts to 3.75 volts.
Example
This example sets the threshold to 1.8 volts for pod 2 (digital channels
D15 through D8).
myScope.WriteString ":POD2:THReshold 1.8"
Query
:POD<N>:THREShold?
The :POD<N>:THReshold? query returns the threshold value for the
specified pod.
Returned Format
[:POD<N>:THReshold] {CMOS50 | CMOS33 | CMOS25 | ECL | PECL | TTL
| DIFF | <value>}<NL>
N O T E
The POD commands only apply to the MSO oscilloscopes.