93
The schematic diagram is shown as below:
Principle
: Connect pin ST_CP of 74HC595 to Raspberry Pi
B18
, SH_CP to
B27
, DS to
B17
, parallel
output ports to 8 segments of the LED segment display. Input data in DS pin to shift register
when SH_CP (the clock input of the shift register) is at the rising edge, and to the memory
register when ST_CP (the clock input of the memory) is at the rising edge. Then you can
control the states of SH_CP and ST_CP via the Raspberry Pi GPIOs to transform serial data
input into parallel data output so as to save Raspberry Pi GPIOs and drive the display.
Experimental Procedures
Step 1: Build the circuit
Содержание Super Kit 3.0
Страница 7: ...4 22 RGB LED 1 23 LED red 8 24 LED white 4 25 LED green 4 26 LED yellow 4 27 NPN Transistor S8050 2 ...
Страница 30: ...27 Also we have drawn a table of the corresponding BCM wiringPi and Name of each pins ...
Страница 78: ...75 Now pull the slide and you can see the two LEDs light up alternately ...