The working principle of traffic lights
Zero input is synchronous active low, low level is valid only the synchronous parallel control terminal, ASM map number control terminal of traffic lights, CO is the carry output, D0 ~ D3 is the parallel data input, Q0 ~ Q 3 is the data output end.
. A second pulse generator is the standard clock signal source timer and controller of the system, the control signal output of the decoder two groups of lights, through a driving circuit driving signal lamp controller, is the main part of the system, it is controlled by the timer and decoder work.
The traffic light control system is mainly composed of controller, timer, decoder and second pulse signal generator.
The timer and system by the second pulse (clock pulse generator is provided) synchronous counter constitution,
The counter uses the integrated circuit 74LS163 to carry on the design, is simpler. 74LS163 is a 4 bit binary synchronous counter. It has the function of synchronous clearing and synchronous setting.
