We have already learned how to use a shift register using 74HC595. In this section, we will try to use a shift register to drive a 7-segment display.
To drive a 7-segment display using a shift register, you can connect 74HC595 to the 7-segment module. The following is the hardware wiring:
74HC595 Q0 to Q6 pins to 7-segment a to b pins
The 74HC595 Q7 pin to the 7-segment DP pin
The 74HC595 VCC pin is connected to Raspberry Pi VCC +3.3 V
The 74HC595 GND pin is connected to Raspberry Pi GND
The 74HC595 DS/Data pin is connected to Raspberry Pi GPIO25 (wPi 6)
The 74HC595 OE pin is connected to Raspberry Pi GPIO GND
The 74HC595 STCP/LATCH pin is connected to Raspberry Pi GPIO24 (wPi 5)
The 74HC595 SHCP/Clock pin is connected to Raspberry Pi GPIO23 (wPi 4)
The 74HC595 MR pin is connected to Raspberry Pi GPIO VCC +3.3 V
You can see that there are resistors on the wiring. These components are used to prevent the higher current flow on you wiring so a resistor...