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Display a Single 7-Segment Digit

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# Seven segment display configuration
segment_mapping = [
    [1, 1, 1, 1, 1, 1, 0],  # 0
    [0, 1, 1, 0, 0, 0, 0],  # 1
    [1, 1, 0, 1, 1, 0, 1],  # 2
    [1, 1, 1, 1, 0, 0, 1],  # 3
    [0, 1, 1, 0, 0, 1, 1],  # 4
    [1, 0, 1, 1, 0, 1, 1],  # 5
    [1, 0, 1, 1, 1, 1, 1],  # 6
    [1, 1, 1, 0, 0, 0, 0],  # 7
    [1, 1, 1, 1, 1, 1, 1],  # 8
    [1, 1, 1, 1, 0, 1, 1]   # 9
]

def draw_digit(digit, x, y, width, height, thickness, color):
    if digit < 0:
        return
    segment_on = segment_mapping[digit]

    # Horizontal segments
    for i in [0, 3, 6]:
        if segment_on[i]:
            if i == 0:  # top
                y_offset = 0
            elif i == 3:  # bottom
                y_offset = height - thickness
            else:  # middle
                y_offset = height // 2 - thickness // 2
            oled.fill_rect(x, y + y_offset, width, thickness, color)

    # Vertical segments
    for i in [1, 2, 4, 5]:
        if segment_on[i]:
            if i == 1 or i == 5:  # upper
                start_y = y
                end_y = y + height // 2
            else:  # lower
                start_y = y + height // 2
                end_y = y + height
            x_offset = 0 if (i == 4 or i == 5) else width - thickness
            oled.fill_rect(x + x_offset, start_y, thickness, end_y - start_y, color)

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# Clock Lab 20: Draw Seven Segments
# this lab uses the fill_rect function to draw the segments
from machine import Pin
import utime
import ssd1306
from utime import sleep, localtime
import config

led = machine.Pin(25, machine.Pin.OUT)

SCL=machine.Pin(config.SPI_SCL_PIN) # SPI CLock
SDA=machine.Pin(config.SPI_SDA_PIN) # SPI Data

RES = machine.Pin(config.SPI_RESET_PIN) # Reset
DC = machine.Pin(config.SPI_DC_PIN) # Data/command
CS = machine.Pin(config.SPI_CS_PIN) # Chip Select

WIDTH = config.DISPLAY_WIDTH
HEIGHT = config.DISPLAY_HEIGHT
spi=machine.SPI(config.SPI_BUS, sck=SCL, mosi=SDA, baudrate=100000)
oled = ssd1306.SSD1306_SPI(WIDTH, HEIGHT, spi, DC, RES, CS)

segmentMapping = [
  #a, b, c, d, e, f, g
  [1, 1, 1, 1, 1, 1, 0], # 0
  [0, 1, 1, 0, 0, 0, 0], # 1
  [1, 1, 0, 1, 1, 0, 1], # 2
  [1, 1, 1, 1, 0, 0, 1], # 3
  [0, 1, 1, 0, 0, 1, 1], # 4
  [1, 0, 1, 1, 0, 1, 1], # 5
  [1, 0, 1, 1, 1, 1, 1], # 6
  [1, 1, 1, 0, 0, 0, 0], # 7
  [1, 1, 1, 1, 1, 1, 1], # 8
  [1, 1, 1, 1, 0, 1, 1]  # 9
];

# digit is the numer to display
# x and y are upper-left-corner
# width and height are the dimensions of the digit
# thickness is the width of the line segments
# color is 1 for white and 0 for black
def drawDigit(digit, x, y, width, height, thickness, color):
  # get a list of the segments that are on for this digit
  segmentOn = segmentMapping[digit];

  # Draw the horizontal segments: top, bottom, middle
  for i in [0, 3, 6]:
    if (segmentOn[i]):
      if (i==0): # top
          yOffset = 0 
      if (i==3):
          yOffset = height - thickness # bottom element
      if (i==6):
          yOffset = height // 2 - thickness // 2# bottom
      # oled.line(x - size, y+yOffset-size, x + size, y+yOffset-size, 1);
      oled.fill_rect(x, y+yOffset, width, thickness, color)

  # Draw the vertical segments ur, lr, ll, ul
  for i in [1, 2, 4, 5]:
    if (segmentOn[i]) :
      # upper vertical lines
      if (i==1 or i==5):
          startY = y
          endY = y + height // 2
      # lower two vertical lines (2=lower right and 4=lower left)
      if (i==2 or i==4):
          startY = y + height // 2
          endY = y + height
      if (i==4 or i==5): xOffset = 0
      if (i==1 or i==2): xOffset = width-thickness

      oled.fill_rect(x+xOffset, startY, thickness, endY-startY, color)

oled.fill(0)
w = 40 # digit width
h = 64 # digit height
x = (WIDTH // 2) - w // 2 # center - width
y = 0 # upper left corner y
t = 8

while True:
    for i in range(0, 10):
        print(i)
        # create an outline on px away from the drawing region
        # oled.rect(x-2, y-2, w+4, h+4, 1)
        # draw one digit
        drawDigit(i, x, y, w, h, t, 1)
        # draw a second digit
        #drawDigit(i, x + w + 4, w, h, t, 1)
        oled.text(str(i), 0, 54, 1)
        oled.show()
        sleep(2)
        oled.fill(0)