Hello.
I am reasonably new to logic circuits and would like some help on my design of the traffic light controller. I have been tasked this project without much prior knowledge and would appreciate help to critique my design.
Some required parts such as the 555 timer and push button circuits have been have been designed and they work.
here is the project requirement:
A traffic light controller produces five output signals.
Three output signals named Veh_Red, Veh_Amber, Veh_Green control the flow of vehicles while the other two signals named Man_Red, Man_Green control the flow of pedestrians. Veh_Red and Man_Green are always asserted at the same time. Similarly, it applied on Veh_Green and Man_Red. Each traffic light indicator will last for seven seconds in the following steps:
1) 7 seconds for Veh_Red and Man_Green
2) 7 seconds for Veh_Green and Man_Red
3) 7 seconds for Veh_Amber
The process is repeated. A push button is used for pedestrians to cross the road. Three seconds after
pressing the push button, the traffic light controller will trigger to the step (3), 7 seconds for
Veh_Amber. So the pedestrians can cross the road after ten seconds pressing the button. A seven
segment display is used to show the remaining time for pedestrians to cross the road. It only works
in Step (1). It is noted that push button should not work during Step (1) and the 3-second waiting
time.
Project Guideline:
: Implement the push button and a three second counter
: Implement the main controller part
: Implement the seven segment display
The main problem i have is that i am not sure of how to ensure that each state lasts for 7 secs and 3 secs .
Heres what i have done so far ( see uploaded pics )
-- created the state diagrams
--output encoding
--current state and next state with input
--simplified using k-maps
I am reasonably new to logic circuits and would like some help on my design of the traffic light controller. I have been tasked this project without much prior knowledge and would appreciate help to critique my design.
Some required parts such as the 555 timer and push button circuits have been have been designed and they work.
here is the project requirement:
A traffic light controller produces five output signals.
Three output signals named Veh_Red, Veh_Amber, Veh_Green control the flow of vehicles while the other two signals named Man_Red, Man_Green control the flow of pedestrians. Veh_Red and Man_Green are always asserted at the same time. Similarly, it applied on Veh_Green and Man_Red. Each traffic light indicator will last for seven seconds in the following steps:
1) 7 seconds for Veh_Red and Man_Green
2) 7 seconds for Veh_Green and Man_Red
3) 7 seconds for Veh_Amber
The process is repeated. A push button is used for pedestrians to cross the road. Three seconds after
pressing the push button, the traffic light controller will trigger to the step (3), 7 seconds for
Veh_Amber. So the pedestrians can cross the road after ten seconds pressing the button. A seven
segment display is used to show the remaining time for pedestrians to cross the road. It only works
in Step (1). It is noted that push button should not work during Step (1) and the 3-second waiting
time.
Project Guideline:
: Implement the push button and a three second counter
: Implement the main controller part
: Implement the seven segment display
The main problem i have is that i am not sure of how to ensure that each state lasts for 7 secs and 3 secs .
Heres what i have done so far ( see uploaded pics )
-- created the state diagrams
--output encoding
--current state and next state with input
--simplified using k-maps
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