import RPi.GPIO as GPIO
import time
# Constants of GPIO port numbers in BCM
SER = 17
RCLK = 27
SRCLK = 10
SRCLR = 9
# 7 segments LED light patterns
# Patern is (a b c ... h dp) to send SER from LSB to MSB
patterns = [0xfc, 0x60, 0xda, 0xf2, 0x66, 0xb6, 0xbe, 0xe0, 0xfe, 0xf6, 0xee, 0x3e, 0x9c, 0x7a, 0x9e, 0x8e]
# Ending process
def destroy():
# Clear all FlipFlops and registers
GPIO.output(SRCLR, GPIO.LOW)
time.sleep(0.001)
GPIO.output(SRCLR, GPIO.HIGH)
# Release resource
GPIO.cleanup()
# Initializing block
GPIO.setmode(GPIO.BCM)
GPIO.setup(SER, GPIO.OUT, initial=GPIO.LOW)
GPIO.setup(SRCLK, GPIO.OUT, initial=GPIO.LOW)
GPIO.setup(SRCLR, GPIO.OUT, initial=GPIO.HIGH)
GPIO.setup(RCLK, GPIO.OUT, initial=GPIO.LOW)
# Clear all segments
GPIO.output(SRCLR, GPIO.LOW)
time.sleep(0.01)
GPIO.output(SRCLR, GPIO.HIGH)
try:
while True:
# Do for each number display
for pattern in patterns:
for n in range(8):
# Input bits from LSB to MSB
# True == 1 == GPIO.HIGH and False == 0 == GPIO.LOW
GPIO.output(SER, (pattern >> n) & 1)
# Send bit to shift register
GPIO.output(SRCLK, GPIO.HIGH)
time.sleep(0.01)
GPIO.output(SRCLK, GPIO.LOW)
# Get parallel data
GPIO.output(RCLK, GPIO.HIGH)
time.sleep(0.01)
GPIO.output(RCLK, GPIO.LOW)
time.sleep(0.5)
except KeyboardInterrupt:
destroy()
