Hi, at my this i created a system for traffic lights and pedestrian way control.

You can also watch my Youtube presentation.

Equipments that used in this project are;
+ MSP430 Chipset
+ GLCD (Nokia 5110)
+ Distance Sensor (HCSR-04)
+ Buzzer
+ LEDs
+ Buttons

Procedure of my system is like this;
I have two counters. One stars 60 to zero , another one counts
30 to zero. If we are in the first time interval ( 60 -> 0 ) cars can use their way
but pedestrians should wait until time is end. We can see the down counting from
the screen. If any person attempts to pass across the street ( from car’s road ),
the distance sensor that located edge of car’s road, will war by buzzer.

After first time interval car’s passed. Another countdown starts. (from 30 -> zero )
Cars should stop and people can pass across the street.

Third past is interrupt section. At the late hours traffic won’t be busy so we don’t need
LCD, sensors, buzzer and etc. We just need a blinking LED for warning. That also reduce
the power consupmtion.

P.s. You can find the port interrupt program and my lcd commands from early posts.

Best wishes.