Frequency counter architecture: Within a digital frequency counter, the timing and control block provides the overall coordination of gating, counting, range selection, and latching—in other words, it supplies the ________ of the instrument.
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Abrains
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BBCD counters
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Cdisplay register
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Dsix different frequency measurement ranges
Answer
Correct Answer: brains
Explanation
Introduction / Context:A frequency counter typically includes input conditioning, a precision time base, counters, latches, and a display interface. These blocks must be orchestrated so that counts occur during a known gate interval, ranges are selected correctly, and results are latched for display. The coordination role belongs to the timing and control block.
Given Data / Assumptions:
- Instrument components: time base, counters (often BCD), gate/enable logic, display registers.
- Timing and control asserts enables, resets, and latches at the correct times.
- Range selection adjusts the gate interval or prescaler to suit input frequency.
Concept / Approach:The “brains” of the counter means the finite-state control that sequences operations: clear counters, open gate, close gate, latch results, update display, optionally average or autorange. Without this coordination, the remaining hardware would not produce stable, accurate readings.
Step-by-Step Solution:
Initialize: assert clear to zero the counters.Measure: open gate for a precise interval derived from the time base.Capture: close the gate and latch count into a display register.Display/Repeat: update indicators and repeat with selected range.Verification / Alternative check:State diagrams in textbooks show these phases; synthesis results reveal a controller FSM generating enables and latches.
Why Other Options Are Wrong:
BCD counters / display register: Data-path elements; they perform counting or storage but do not orchestrate.six different frequency measurement ranges: A feature controlled by the brains, not the brains themselves.Common Pitfalls:Letting counters run while latching, causing metastability; misaligned gate timing; ignoring time-base accuracy.
Final Answer:brains