Scripts for controlling a quad 7-segment display via a Rasyberry Pi Pico using Micropython. Both Direct GPIO and via shift registers.

quad-7-segment-shift.py

from machine import Pin
import time
import _thread

display_number = 0
padding = True

dataPIN1 = 18
dataPIN2 = 20
latchPIN2 = 19  
latchPIN1 = 17
clockPIN = 16


clockPIN=Pin(clockPIN, Pin.OUT)
dataPIN1=Pin(dataPIN1, Pin.OUT)
latchPIN1=Pin(latchPIN1, Pin.OUT)
dataPIN2=Pin(dataPIN2, Pin.OUT)
latchPIN2=Pin(latchPIN2, Pin.OUT)

numbers = {
  "0": "11111100",
  "1": "01100000",
  "2": "11011010",
  "3": "11110010",
  "4": "01100110",
  "5": "10110110",
  "6": "10111110",
  "7": "11100000",
  "8": "11111110",
  "9": "11100110"
}

coms = ["01111111", "10111111", "11011111", "11101111", "11110111"]


# Thanks to https://peppe8o.com/how-to-use-74hc595-shift-register-with-raspberry-pi-pico-and-micropython/
def shift_update(input,data,clock,latch):
  """
  Send update to shift register
  """


  #put latch down to start data sending
  clock.value(0)
  latch.value(0)
  clock.value(1)

  
  #load data in reverse order
  for i in range(7, -1, -1):
    clock.value(0)
    data.value(int(input[i]))
    clock.value(1)

  #put latch up to store data on register
  clock.value(0)
  latch.value(1)
  clock.value(1)


def display_number_led(num: int, padding=False):
  """
  Displays a four digit number on the 7 segment display
  Padding=true will pre-pend zeroes.
  """

  n = str(num)

  # Pad with zeroes if requested
  if padding:
    if len(n) < 4:
      t = 4 - len(n)
      for i in range(t):
        n = "0" + n


  # Display the number
  for i in range(4):
    shift_update(numbers[n[i]],dataPIN1,clockPIN,latchPIN1)
    time.sleep(0.001)
    shift_update(coms[i],dataPIN2,clockPIN,latchPIN2)

    # Clear the display to "update" a bit slower for the human eyes
    shift_update("11111111",dataPIN2,clockPIN,latchPIN2)


def display_number_thread():
  """
  Displays a four digit number on the 7 segment display
  Padding=true will pre-pend zeroes.
  """
  from machine import Pin

  while True:
    display_number_led(display_number, padding=padding)




if __name__ == "__main__":

  # Start the display thread
  second_thread = _thread.start_new_thread(display_number_thread, ())

  count = 0
  while True:
    display_number = count
    count += 1
    if count > 9999:
      count = 0
    
    time.sleep(0.1)

quad-7-segment.py

from machine import Pin
import time
import _thread

##########

led = Pin("LED", Pin.OUT)

# Top, Top-Right, Bottom-Right, Bottom, Bottom-Left, Top-Left, Middle, Dot, Colon
# A, B, C, D, E, F, G, DP
# Pico GP pins
LED_pins = [9, 7, 26, 28, 5, 8, 22, 27]
COLON_pin = 6
COLON_enable = False

LED_mappings = {"A": 9, "B": 7, "C": 26, "D": 28, "E": 5, "F": 8, "G": 22, "DP": 27}
LED_names = LED_mappings.keys()
numbers = {
    0: ["A", "B", "C", "D", "E", "F"],
    1: ["B", "C"],
    2: ["A", "B", "D", "E", "G"],
    3: ["A", "B", "C", "D", "G"],
    4: ["B", "C", "F", "G"],
    5: ["A", "C", "D", "F", "G"],
    6: ["A", "C", "D", "E", "F", "G"],
    7: ["A", "B", "C"],
    8: ["A", "B", "C", "D", "E", "F", "G"],
    9: ["A", "B", "C", "F", "G"],
}

# Digit 1, Digit 2, Digit 3, Digit 4, Colon
# Pico GP pins
COM_pins = [15, 14, 13, 11, 12]
display_digit = [1, 2, 3, 4]


##########


def disable_all_compins() -> None:
    """
    Disables all COM pins
    """
    for pin in COM_pins:
        Pin(pin, Pin.OUT).value(1)


def disable_other_compins(digit: int) -> None:
    """
    Disables all COM pins except the one specified
    """
    for pin in COM_pins:
        if pin != COM_pins[digit]:
            Pin(pin, Pin.OUT).value(1)
        else:
            Pin(pin, Pin.OUT).value(0)


def clear_digit(digit: int) -> None:
    """
    Clears the digit by turning off all LEDs
    """
    # Enable Digit requested by tying Digit COM PIN to LOW
    Pin(COM_pins[digit], Pin.OUT).value(0)

    for num in LED_pins:
        Pin(num, Pin.OUT).value(0)


def clear_all_digits() -> None:
    """
    Clears all digits by turning off all LEDs
    """
    for digit in range(4):
        clear_digit(digit)

    disable_all_compins()


def enable_colon() -> None:
    """
    Enables the colon by tying the COLON pin to LOW
    """
    Pin(COM_pins[-1], Pin.OUT).value(0)
    Pin(COLON_pin, Pin.OUT).value(1)


def disable_colon() -> None:
    """
    Disables the colon by tying the COLON pin to HIGH
    """
    Pin(COM_pins[-1], Pin.OUT).value(1)
    Pin(COLON_pin, Pin.OUT).value(0)


def draw_number_on_digit(number: int, digit: int, dot: bool = False) -> None:
    """
    Draws a number on a single digit by tying the COM pin to LOW
    And drawing the number on the LEDs
    """

    # Disable all other digits
    disable_other_compins(digit)

    # Clear the digit so we dont get weirdness
    Pin(COM_pins[digit], Pin.OUT).value(0)

    for num in numbers[number]:
        Pin(LED_mappings[num], Pin.OUT).value(1)

    if dot:
        Pin(LED_mappings["DP"], Pin.OUT).value(1)


def draw_number_four_digits(
    number: list[int],
    dots: list[bool] = [False, False, False, False],
    colon: bool = False,
) -> None:
    """
    Takes a four digit integer and draws it on the display
    """

    # Draw each digit
    for i in range(4):
        draw_number_on_digit(number[i], i, dots[i])
        clear_digit(i)

        if colon:
            enable_colon()
            disable_colon()
        else:
            disable_colon()


def draw_four_thread() -> None:
    """
    Takes a four digit integer and draws it on the display
    """
    from machine import Pin

    while True:
        draw_number_four_digits(
            display_digit, dots=[False, False, False, False], colon=COLON_enable
        )


##########

if __name__ == "__main__":
    # Enable LED to show that something is happening
    led = Pin("LED", Pin.OUT)
    led.value(1)

    # Start the display thread
    second_thread = _thread.start_new_thread(draw_four_thread, ())

    count = 0
    while True:
        c = str(count)

        if len(c) < 4:
            t = 4 - len(c)
            for i in range(t):
                c = "0" + c

        display_digit = [int(i) for i in c]
        # draw_number_four_digits(display_digit)

        count += 1
        if count >= 9999:
            count = 0

        time.sleep(0.1)