SunFounder ESP32

SunFounder ESP32 Starter Kit
(continued from previous page)
rclk.off()
# Iterate through each bit (from 7 to 0)
for bit in range(7, -1, -1):
# Extract the current bit from the input data
value = 1 & (dat >> bit)
# Set the SRCLK pin to low
srclk.off()
# Set the value of the SDI pin
sdi.value(value)
# Clock the current bit into the shift register by setting the SRCLK pin to high
srclk.on()
# Latch the data into the storage register by setting the RCLK pin to high
rclk.on()
# Continuously loop through the numbers 0 to 9 and display them on the 7-segment display
while True:
for num in range(10):
hc595_shift(SEGCODE[num]) # Shift the segment code for the current number into␣
˓→the 74HC595
time.sleep_ms(500) # Wait 500 milliseconds before displaying the next number
When the script is running, you will be able to see the LED Segment Display display 0~9 in sequence.
How it works?
In this project, we are using the hc595_shift() function to write the binary number to the shift register.
Suppose that the 7-segment Display display the number “2”. This bit pattern corresponds to the segments f, c and dp
being turned off (low), while the segments a, b, d, e and g are turned on (high). This is “01011011” in binary and
“0x5b” in hexadecimal notation.
Therefore, you would need to call hc595_shift(0x5b) to display the number “2” on the 7-segment display.
328 Chapter 3. For MicroPython User