kopia lustrzana https://github.com/pimoroni/pimoroni-pico
91 wiersze
2.6 KiB
Python
91 wiersze
2.6 KiB
Python
# This example takes the temperature from the Pico's onboard temperature sensor, and displays it on Pico Explorer, along with a little pixelly graph.
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# It's based on the thermometer example in the "Getting Started with MicroPython on the Raspberry Pi Pico" book, which is a great read if you're a beginner!
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import machine
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import time
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from picographics import PicoGraphics, DISPLAY_PICO_EXPLORER
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# set up the hardware
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display = PicoGraphics(display=DISPLAY_PICO_EXPLORER)
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sensor_temp = machine.ADC(4)
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# set up constants for drawing
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WIDTH, HEIGHT = display.get_bounds()
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BLACK = display.create_pen(0, 0, 0)
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WHITE = display.create_pen(255, 255, 255)
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conversion_factor = 3.3 / (65535) # used for calculating a temperature from the raw sensor reading
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temp_min = 10
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temp_max = 30
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bar_width = 5
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temperatures = []
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colors = [(0, 0, 255), (0, 255, 0), (255, 255, 0), (255, 0, 0)]
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def temperature_to_color(temp):
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temp = min(temp, temp_max)
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temp = max(temp, temp_min)
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f_index = float(temp - temp_min) / float(temp_max - temp_min)
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f_index *= len(colors) - 1
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index = int(f_index)
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if index == len(colors) - 1:
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return colors[index]
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blend_b = f_index - index
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blend_a = 1.0 - blend_b
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a = colors[index]
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b = colors[index + 1]
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return [int((a[i] * blend_a) + (b[i] * blend_b)) for i in range(3)]
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while True:
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# fills the screen with black
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display.set_pen(BLACK)
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display.clear()
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# the following two lines do some maths to convert the number from the temp sensor into celsius
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reading = sensor_temp.read_u16() * conversion_factor
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temperature = 27 - (reading - 0.706) / 0.001721
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temperatures.append(temperature)
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# shifts the temperatures history to the left by one sample
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if len(temperatures) > WIDTH // bar_width:
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temperatures.pop(0)
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i = 0
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for t in temperatures:
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# chooses a pen colour based on the temperature
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TEMPERATURE_COLOUR = display.create_pen(*temperature_to_color(t))
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display.set_pen(TEMPERATURE_COLOUR)
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# draws the reading as a tall, thin rectangle
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display.rectangle(i, HEIGHT - (round(t) * 4), bar_width, HEIGHT)
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# the next tall thin rectangle needs to be drawn
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# "bar_width" (default: 5) pixels to the right of the last one
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i += bar_width
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# draws a white background for the text
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display.set_pen(WHITE)
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display.rectangle(1, 1, 100, 25)
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# writes the reading as text in the white rectangle
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display.set_pen(BLACK)
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display.text("{:.2f}".format(temperature) + "c", 3, 3, 0, 3)
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# time to update the display
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display.update()
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# waits for 5 seconds
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time.sleep(5)
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