TTL Stoplight Controller

This is a stoplight controller I built for my Eastern Washington University digital hardware class. Our group was one of two groups to complete the task. (the glicth in the video red-green w/ no yellow was due to a bouncing switch) This was one of our most challenging digital designs. Our approach was a 555 timer driven counter to keep track of aprox # of seconds. This count was passed to a second counter which kept track of the "intersection state" (side Red main Green, side Red main Yellow, and side Green main Red Side Yellow) The counter was used to force a time out or minimum time on for the main Green and side Green conditions. By the end of the project we only had physical space for 2 more TTL chips!


Muskrat Micros - Embedded Solutions for the Masses