Summary

You built the rope: the factory releases a part by itself only when the bottleneck needs work. All the new electronics fits in a few lines:

  • out — two CD4029 counting down: CLOCK = OUTH (IR after Herbie), UD = 0 — they hold −out;
  • buffer — two CD4008: Q = R + H = in − out, where R is «released» from FL-01;
  • buffer below the goal — two CD4585 in a cascade: LOW = Q < G;
  • rope — three gates: RELR = RELS · (LOW + NOT ROPE), the source listens to RELR.
sourceOUT → R0…R7IR after HerbieOUTH2 × CD4029 ↓H0…H72 × CD4008Q = R + H2 × CD4585Q < Ggoal G4 switches3 gatesRELRLOWropebuffer display
The kit’s new electronics: the buffer counter (in − out), the comparison with the goal and the rope to the source.

What's next

  • Set goal 15 (all four switches). How does the rope differ from «push» then?
  • Make machine 5 slow instead of Herbie, and leave the IR pair and the rope alone. What does the buffer show? Where should the IR pair stand now?
  • Give a die to all five machines. Is goal 6 enough?
  • Turn SLOW and ROPE on together. What happens and why?