D.3 Mode B Waveforms
Software-Triggered Strobe with Level Gating
Mode B is identical to Mode A except that source edges are counted only when the assigned gate is active. The counter must be armed before counting can occur. Once armed, the counter will count all source edges that occur while the gate is active and disregard those edges that occur while the gate is inactive.
This permits the gate to turn the counting process on and off. On each TC the counter will reload from the Load register and automatically disarm itself, inhibiting further counting until a new ARM command is issued.
SOURCE
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GATE |
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COUNT | X | L | K+1 | K | 2 | 1 | 0 | L | |||
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TC OUTPUT
TC TOGGLED
OUTPUT
Mode B Waveforms
48 |
