Tektronix 6 series, Печатная инструкция

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Acquisition mode
FastFrame
™ segmented memory acquisition
uses multiple trigger events to capture widely
spaced events of interest at high sample rates
while conserving acquisition memory. Capturing
thousands of frames is possible, allowing analysis
of long-term trends and changes in the bursting
signal.
Roll Mode scrolls sequential waveform points
across the display in a right-to-left rolling motion.
Roll mode starts automatically when the timebase
is set to ≥40 ms/div. Roll mode works at sample
rates up to 10 MS/s.
FastFrame concepts
FastFrame
™
lets you to capture only the waveform, or waveform segment of interest, eliminating the dead space between
conditions of interest. Each captured event is stored in its own numbered memory segment. Multiple memory segments, or
frames, can then be viewed individually in the order they were captured, or layered to show their similarity and contrast.
Advantages of using FastFrame include:
■
The high waveform capture rate increases the probability of capturing infrequent events
■
The waveform detail is preserved by using high sample rates
■
The events are captured while ignoring the dead time between them, ensuring efficient use of the record length memory
■
The segments can be quickly and visually compared to determine if an anomaly “sticks out” of the overlaid stack
Each frame can be viewed individually and you can scroll through them by selecting frame numbers with a mouse, virtual keypad
or the multi-purpose knob on the instrument’s main console. When a particular frame of interest is identified, you can use the
instrument’s features to characterize, measure, zoom and analyze the waveform in detail.
To quickly see anomalies that stand out from the common shape of the waveform, multiple frames can be overlaid to show
common and outlying points. Enabling Overlay Frames in the FastFrame configuration menu overlays all frames in the current
acquisition using color to highlight how frequently the points are overlaid on each other.
You can also view multiple signal input frames simultaneously by using stacked waveform display mode. When you scroll
through the frames, the oscilloscope displays the acquisition frame for all waveforms captured.
Debugging signal errors with time stamps
FastFrame mode provides a different type of functionality for digital designers. For example, if your processor system is being
infrequently interrupted, it can be difficult to gather timing information with an oscilloscope. If you don’t know when or how
frequently the event occurs, you can’t set up the instrument in normal acquisition mode and be assured of capturing the
information you need.
FastFrame mode can do this easily by providing information on the interval between frames. For example, the active high
interrupt strobe on a microprocessor system is measured to be roughly 100 nanoseconds wide, so we set up the oscilloscope to
capture 100 frames of 1250 points. In this example, the shape of the pulse is not of particular interest. We are, however,
interested in the time of the pulses’ rising edges.
After turning FastFrame on and selecting “Single Acquisition” to capture 100 frames, you use the readouts in the FastFrame
results badge to compare the time stamp data at the trigger point. The “Reference Frame” was chosen to be the first interrupt
pulse and the “Selected Frame” is the fourth pulse. The time difference between these pulses is shown in the Delta readout on
the badge.
Waveform acquisition concepts
414 MSO54, MSO56, MSO58, MSO58LP, MSO64 Help