1. Interfacing of Traffic light controller

2. HARDWARE FOR TRAFFIC LIGHT CONTROL
12 electric bulbs
Port A is used to control lights on N-S road and Port B is used to control lights on W-E road.
Electric bulbs are controlled by relays.
8255 pins are used to control relay on-off action with the help of relay driver circuits. The driver circuit includes 12 transistors to drive 12 relays.

3. Interfacing of Traffic light controller

4. Software for traffic light controller

6. Program:- OUT 83H (CR) START: MVI A, 09H OUT 80H (PA) MVI A, 24H
OUT 81H (PB)
CALL DELAY1
MVI A, 12H
OUT (80H) PA
OUT (81H) PB
CALL DELAY2
MVI A, 24H
OUT 80H (PA)
MVI A, 09H
OUT 81H (PB)
CALL DELAY1
MVI A, 12H
OUT PA
OUT PB
CALL DELAY2
JMP START