Question

4: Develop a state machine diagram for a traffic light controller that works as follows: A timing signal T is the input to the controller. T defines the yellow light interval, as well as the changes of the red and green lights. The outputs tothe signals are defined by the following:GN Green Light, North/South SignalYN Yellow Light, North/South Signal RN Red Light, North/South SignalGE Green Light, East/West SignalYE Yellow Light, East/West SignalRE Red Light, East/West SignalWhile T 0 the green light is on for one signal and the red light for the other. With T 1, the yellow light is on for the signal that was previously green, and the signal that was previously red remains red. When T becomes0, the signal that was previously yellow becomes red, and the signal that was previously red becomes green. This pattern of alternating changes in color continues. Assume that the controller is synchronous with a clock that changes much more frequently than input T 5: Develop a C++ program that demonstrates the behavior of the circuit in question 4. The code should be submitted as a CPP file or a link to the online IDE.

Answer 1

Step 1 of 4 To complete 7-38P, we are given the following table: Output Light Controlled GN Green Light, North/South Signal YN Yellow Light, North/South Signal RN Red Light, North/South Signal Green Light, East/West Signal GE Yellow Light, East/West Signal YE RE Red Light, East/West Signal We are to find the state machine diagram for the circuit that controls these lights. We read that while T 0, the green light is on for one signal and red light for the other. This is our initial state. If T 1, we will proceed to our next state. As with any state diagram we set it up with a reset switch and conditions. We will start with GN and RE since they come first on the table:

GN, RE Reset S1 T T S2

Next, we read that when we enter our second state, the light that was green becomes yellow and the red light stays red for as long as T = 1. When T 0, we proceed to our third state. So in our case GN will become YN and RE will stay RE GN, RE Reset S1 T T YN, RE S2 T T S3

Step 3 of 4 Once in state 3, the light that was previously yellow becomes red, and the light that was red 1, we proceed to our fourth and final state. In our becomes green for as long as T 0. When T case YN will become RN, and RE will become GE.

GN, RE Reset S1 T YN, RE S2 T T RN, GE S3 T T S3

Finally, in state 4, the light that was previously green becomes yellow, and the light that was red stays red as long as T 1. When T 0 we return to our initial state and start the process again. In our case, RN will stay as RN and GE will become YE. This will complete our state machine diagram for the circuit

GN, RE Reset S1 T YN, RE S2 T RN, GE S3 RN, YE T T S3 T