MDO3000 Programmer Manual.pdf - 第252页
Commands Listed in A lphabetical Order channel that ha s no probe attached or a probe that does not support DCREJect coupling attached results in a settings conflict error event and the coupli ng remains unchanged. Exampl…
Commands Listed in Alphabetical Order
CH<x>:BANdwi
dth
This command specifies the selectable low-pass bandwidth limit filter for channel
<x>, where x is the channel number (1–4).
Available bandwidth limits vary by model, and are also influenced by attached
probes. Furthermore, some oscilloscope models support options to increase
the analog bandwidth. The presence of those options also affects the available
bandwidth limits.
To see what the available bandwidth limits are, on the UI, push the relevant
channel's front panel button and the push the Bandwidth lower menu button, and
see what bandwidths are listed in the side menu.
Group
Vertical
Syntax
CH<x>:BANdwidth {FULl|<NR3>}
CH<x>:BANdwidth?
Arguments
FULl disables any optional bandwidth limiting. The specified channel operates
at its maximum attainable bandwidth.
<NR3> is a double-precision ASCII string. The oscilloscope rounds this value to
an available bandwidth using geometric rounding, and then uses this value to
set the upper bandwidth limit.
Examples
CH1:BANDWIDTH 20E6 sets the bandwidth of channel 1 to 20 MHz.
CH<x>:COUPling
This command specifies the input attenuator coupling setting for channel <x>,
where x is the channel number (1–4).
Group
Vertical
Syntax
CH<x>:COUPling {AC|DC|DCREJect}
CH<x>:COUPling?
Arguments
AC sets channel <x> to AC coupling.
DC sets channel <x> to DC coupling.
DCREJect sets channel <x> to DC Reject coupling when a probe that supports
DC Reject coupling is attached. Attempting to set the coupling to DCREJect for a
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-221
Commands Listed in Alphabetical Order
channel that ha
s no probe attached or a probe that does not support DCREJect
coupling attached results in a settings conflict error event and the coupling
remains unchanged.
Examples
CH2:COUPLING AC sets channel 2 to AC coupling.
CH3:COUPling? might return :CH3:COUPling DC indicating that channel 3
is set to DC coupling.
CH<x>:DESKew
This command specifies the deskew time for channel <x>, where x is the
channel number (1–4). You can adjust the deskew time to add an independent,
channel-based delay time to the delay (set by the horizontal position control and
common to all channels) from the common trigger point to first sample taken for
each channel. This lets you compensate individual channels for different delays
introduced by their individual input hook ups.
Group
Vertical
Syntax
CH<x>:DESKew <NR3>
CH<x>:DESKew?
Arguments
<NR3> is a floating point number that specifies the deskew time for channel <x>,
ranging from -100 ns to +100 ns with a resolution of 1 ps.
Examples
CH4:DESKew 5.0E-9 sets the deskew time for channel 4 to 5 ns.
CH2:DESKew? might return :CH2 :DESKEW 2.00 00E-09 ind
icating that the
deskew time for channel 2 is set to 2 ns.
CH<x>:INVert
This command specifies the invert function for channel <x>, where is the channel
number (1–4) . When on, the invert function inverts the waveform for the
specified channel.
NOTE. This command inverts the waveform for display purposes only. The
oscilloscope does not use an inverted waveform for triggers or trigger logic inputs.
Group
Vertical
2-222 MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual
Commands Listed in Alphabetical Order
Syntax
CH<x>:INVert {
ON|OFF}
CH<x>:INVert?
Arguments
OFF sets the invert function for channel <x> to off.
ON sets the invert function for channel <x> to on.
Examples
CH4:INVert ON inverts the waveform on channel 4.
CH2:INVert? might return :
CH2:INVERT 0
indicating that channel 2 is not
inverted.
CH<x>:LABel
This command specifies the waveform label for channel <x>, where x is the
channel number (1–4).
Group
Vertical
Syntax
CH<x>:LABel <Qstring>
CH<x>:LABel?
Arguments
<Qstring> is an alphanumeric string of text, enclosed in quotes, that contains the
text label information for the channel <x> waveform. The text string is limited
to 30 characters.
CH<x>:OFFSet
This command specifies the vertical offset for channel <x>, where x is the channel
number (1–4).
This command offsets the vertical acquisition window (moves the level at the
vertical center of the acquisition window) for the specified channel. Visualize
offset as scrolling the acquisition window towards the top of a large signalfor
increased offset values, and scrolling towards the bottom for decreased offset
values. The resolution of the vertical window sets the
offset increment for this
control.
Offset adjusts only the vertical center of the acquis
ition window for channel
waveforms to help determine what data is acquired. The oscilloscope always
displays the input signal minus the offset value.
The channel offset range depends on the vertical scale factor.
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-223