- The inputs (*IN) are open hi.
- The inputs are activated by pulling them to ground
- The inputs source 12mA when connected to ground
- A 2.2KOhm resistior pulls them well to ground.
- The output DOUT pulls to ground when signal is red
- YIN, RIN and DIN have effect immediately
- When DIN is set hi again the signal goes to green via yellow. The yellow period is influenced via a timer.
In the center there is a PIC that does the logic.
The signal is connected via RJ12 J3.
- The N scale signal has 3 aspects and needs thus 4 wires.
- Pin 1 and 6 of the RJ12 (R1 to AUX1 and R15 to PIC) are not connected to the signal
- The signal has common ground.
- The resistors R12,R13,R14 that are matched to the signals are on the signal control PCB, not part of the signal itself
- I did not check which color was which pin in J3.