Design a circuit capable to store short messages and to display them as a scrolling marquee on the four 7-segment LEDs.
esign a circuit that can store and display an arbitrary messagewhich has been entered character by character by the user. The characters will be entered using the 8DIP. For simplicity, you may assume that the total length of the entered message will be no longer than 20 characters. To remain consistent you must use the following mappings for the DIP switches:
SW7 -segA, SW6 -segB, SW5 -segC, SW4 -segD, SW3 -segE, SW2 -segF, SW1 –segG, SW0 –segDP
Use the three push-buttons to determine the state of your machine. All possible states of the machine are given below:
In other words, when (BTN2,BTN1,BTN0) =(110),the user modifies the switches to the letter they want to be loaded and stored. Then, when (BTN2,BTN1)=(11) andBTN0 goes from 0 to 1, the letter is loaded and stored into the proper register. To load and store the next letter the user only needs to set BTN0 = 0 again (let go of the pushbutton), modify the switches, and then to switch the BTN0 from 0 to 1. These actions take place as long as the user wants to introduce letters or the blank character (the blank character is simply an "empty" character, when nothing is displayed by the 7-segment LED).