Football game score display circuit

This device can be used in industrial, mining and school basketball courts to accumulate game scores on the console and display the scores on the display screen. This circuit uses ordinary CMOS integrated circuits and is easy to make by yourself. The main circuit is shown in Figure 1. IC1 and IC2 are decimal up/down counters, which form the ones and tens digits of the fraction respectively. IC3 and IC4 are 7-segment decoding circuits, which translate the decimal digital signals of IC1 and IC2 into 7-segment codes that can display numbers from 0 to 9. IC5 is the hundredth digit of the score. It has only two states for the JK flip-flop, so the maximum score of this circuit is 199 points. S1 is the extra point switch. Each time it is pressed, it generates a pulse signal that causes IC1 to count once. S2 is a subtraction switch, and each time it is pressed, it counts down once. The carry or borrow signal of IC1 is automatically passed to IC2 to count. S3 is the clearing switch. Press S3 to display "000". R1, C1, R2, and C2 are set to prevent switch jitter. This is because the switch will jitter multiple times when it is turned on or off, causing the circuit to miscount, so a resistor-capacitor component is added to eliminate the jitter of the switch. The output of each segment of the 7-segment code a~g is based on the transistor drive circuit shown in Figure 3. Each section of the A to G display section is composed of multiple light-emitting diodes connected in parallel. The number of light-emitting diodes in each section can be determined according to the screen size, generally about 10. The entire screen layout is shown in Figure 2. Comments on the Fujian Shaoping experiment: This experimental circuit can work normally after installation and plays a scoring role. The principle is simple and easy to succeed. However, since all CMOS circuits are used during installation, the power supply should be disconnected for welding to prevent damage to the CMOS circuit.