Flip-flops are edge-triggered and hold state, which the combinational settle
kernel cannot model alone. buildDigitalNetwork now gives each flip-flop explicit
state + rising-CLK-edge detection (reusing the LogicGateParts sample semantics):
sample the data nets on the edge, drive Q + Qbar. Because a flip-flop only
updates on the clock edge, a Q->D / Q->CLK feedback (counter / shift register)
does not oscillate the settle loop. isAllDigital now accepts a gate OR a
flip-flop, so pure sequential circuits qualify.
Test digitalgate-sequential (4): D (capture + hold), T (toggle), JK
(hold/set/reset/toggle), and a 2-bit ripple counter (FF0.Qbar clocks FF1)
counting 1,2,3,0,1 - impossible on the SPICE path (no edge detection at DC, no
SPICE mapper). The controller already routes all-digital circuits through
buildDigitalNetwork, so a board-less counter/shift-register example would run
live; authoring those gallery examples is the only follow-up. Full digitalgate
+ examples-digital + circuit-simulation-service suites green (127 tests).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
David Montero Crespo