I'm trying to build a 4-way traffic light controller in NI Multisim, using the 555 timer and a decade counter (no microcontrollers allowed). I used this as reference: https://circuits-diy.com/four-way-traffic-light-circuit-using-555-timer-ic/
Upon simulating this circuit, the 4 LEDs farthest to the right lit up, and then the simulation stopped due to a "convergence issue".
Upon analysing, I came to the conclusion that the connections of the 555 IC weren't correct for it to be used as an astable multivibrator. There should be a capacitor between pin 5 (control pin) and ground, instead of a capacitor between Vcc and ground.
Is the large initial pulse the cause for the error? It has a time period of about 190 ms. Subsequent pulses have a period of about 148 ms, which matches with the formula $$0.693(R1+2R2)C$$
If yes, how exactly can we fix this?
LEDs 7,8,9,10 light up successfully because upon generation of the first pulse, Q0 is high. But something seems to be wrong subsequently.
Also, the materials required section of the website states that 3 1k and 3 10k resistors are required, but the diagram only uses 1 of each....is the diagram missing resistors?
Edit: Something I noticed with the scope: Magnitude wise , the initial pulse seems correct (10v),and the subsequent pulses are significantly less than 10v. But time period-wise, the first pulse seems incorrect (~190 seconds), and the rest (~147 seconds) seem to be within agreement of the theoretical calculation...