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Digital logic (gates / K-map / truth table) templates

Physics — Logic: Johnson counter

A twisted-ring counter feeding back the inverted output.

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Template previewDigital logic (gates / K-map / truth table)
Johnson (twisted-ring) counterCLKF0F1F2INVQ0Q1Q2Sequential — `F0` then `F1` then `F2` then `INV` then `F0` is a feedback loop, so this circuit has no…`F0` is a NOT with 2 wires into it — `CLK`, `INV` — and a NOT has exactly one input. The figure draws the one-input …This circuit has feedback: `F0` then `F1` then `F2` then `INV` then `F0`. That makes it SEQUENTIAL — its outputs dep…

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title "Johnson (twisted-ring) counter"
type gates
input CLK at (0,2)
gate NOT F0 at (2,0)
gate NOT F1 at (5,0)
gate NOT F2 at (8,0)
gate NOT INV at (8,3)
output Q0 at (3,2)
output Q1 at (6,2)
output Q2 at (9,2)
wire CLK F0
wire F0 F1
wire F1 F2
wire F2 INV
wire INV F0
wire F0 Q0
wire F1 Q1
wire F2 Q2