This project is based on Microcontroller M68HC11A8. The Runway Lights project give a miniaturized representation of a runway lighting system, in airports for secure landing of night flights. This helps the pilot to locate and align to the direction of runway.
To represent such a system, LED is used as light source. They are driven through transistorized circuit for current stability. Since the transistor is inverting, we have to supply a binary 0 to turn LED on. The program loads required value to accumulator A and copies it to Port B. For example, to glow two LED at bottom most row, place 0x7E at Port B (refer program at label L1).
The circuit can be modified for better usage by replacing given transistors by power transistors and high power relays or TRIAC instead of LED. The relays or TRIAC can be used to drive high intensity halogen bulbs as in real system. A real Runway Light system may require more number of lights instead of eight LED shown here.
The source code written either in C or Assembly language can be viewed from the
code editor window.