Introduction / Context:
Digital storage oscilloscopes (DSOs) sample incoming signals into a finite acquisition memory. What happens when that memory is full depends on the acquisition mode, trigger mode, and instrument settings. The absolute claim that the next point is always lost oversimplifies DSO behavior and is generally false.
Given Data / Assumptions:
- Finite memory depth determines maximum record length at a given sample rate.
- Common modes: single (stop on trigger), run/stop, segmented memory, roll/streaming, circular buffer.
- Triggers and acquisition control affect capture/overwrite policies.
Concept / Approach:
Many DSOs use circular buffering: the instrument continuously writes samples and, upon filling the buffer, wraps around to overwrite the oldest data. In single-shot “stop on full/stop on trigger” modes, the instrument halts acquisition at memory full rather than discarding a specific “next point.” Segmented memory can capture multiple triggered segments efficiently without losing points between segments. Therefore, saying the next data point is necessarily lost is inaccurate; behavior is mode-dependent.
Step-by-Step Solution:
Consider circular (rolling) mode: after filling, the write pointer wraps; no “lost next point,” just continuous overwrite of oldest samples.Consider single acquisition: the scope stops once the record is complete; no new point is taken at all.Consider segmented memory: multiple short records are stored sequentially; inter-segment gaps are controlled, not arbitrary losses.
Verification / Alternative check:
Check specific DSO manuals: acquisition modes explicitly define wrap/stop/segment behavior when memory limits are reached.
Why Other Options Are Wrong:
Correct: Overgeneralizes; many modes avoid “losing the next point” by design.True only in stop-on-full mode: Even here the scope stops; it does not “lose” a specific point.Depends only on probe attenuation: Probe attenuation affects scaling/bandwidth, not memory policy.
Common Pitfalls:
Assuming one vendor’s default mode represents all scopes.Ignoring segmented acquisition which optimizes memory for bursty signals.
Final Answer:
Incorrect
Discussion & Comments