micro:bit Micropython API¶

微比特模块¶

与硬件交互直接相关的一切都存在于microbit模块中。为了便于使用，建议您使用以下命令启动所有脚本：

from microbit import *

以下文档假定您已完成此操作。

有几个函数可以直接使用：

# sleep for the given number of milliseconds.
sleep(ms)
# returns the number of milliseconds since the micro:bit was last switched on.
running_time()
# makes the micro:bit enter panic mode (this usually happens when the DAL runs
# out of memory, and causes a sad face to be drawn on the display). The error
# code can be any arbitrary integer value.
panic(error_code)
# resets the micro:bit.
reset()
# sets the output volume (0-255) of the micro:bit speaker **V2** and
# external speaker or headphones connected to the edge connector pins.
set_volume(128)    # V2

其余功能由 microbit 模块中的对象和类提供，如下所述。

请注意，API 仅公开整数（即不需要浮点数，但可以接受它们）。因此，我们使用毫秒作为标准时间单位

笔记

您可以通过编写help('modules') REPL来查看所有可用模块的列表。

纽扣¶

有2个按钮：

button_a
button_b

它们都是对象并具有以下方法：

# returns True or False to indicate if the button is pressed at the time of
# the method call.
button.is_pressed()
# returns True or False to indicate if the button was pressed since the device
# started or the last time this method was called.
button.was_pressed()
# returns the running total of button presses, and resets this counter to zero
button.get_presses()

展示¶

LED显示屏通过显示对象暴露：

# gets the brightness of the pixel (x,y). Brightness can be from 0 (the pixel
# is off) to 9 (the pixel is at maximum brightness).
display.get_pixel(x, y)
# sets the brightness of the pixel (x,y) to val (between 0 [off] and 9 [max
# brightness], inclusive).
display.set_pixel(x, y, val)
# clears the display.
display.clear()
# shows the image.
display.show(image, delay=0, wait=True, loop=False, clear=False)
# shows each image or letter in the iterable, with delay ms. in between each.
display.show(iterable, delay=400, wait=True, loop=False, clear=False)
# scrolls a string across the display (more exciting than display.show for
# written messages).
display.scroll(string, delay=400)

声音事件V2¶

声音事件描述了麦克风听到的声音的变化：

# Value to represent the transition of sound events, from `quiet` to `loud`
# like clapping or shouting.
SoundEvent.LOUD = SoundEvent('loud')
# Value to represent the transition of sound events, from `loud` to `quiet`
# like speaking or background music.
SoundEvent.QUIET = SoundEvent('quiet')

话筒 V2¶

麦克风是通过麦克风对象访问的：

# Returns the name of the last recorded sound event.
current_event()
# A sound event,  such as `SoundEvent.LOUD` or `SoundEvent.QUIET`.
# Returns`true` if sound was heard at least once since the last
# call, otherwise `false`.
was_event(event)
# Returns a tuple of the event history. The most recent is listed last.
# Also clears the sound event history before returning.
get_events()
# The threshold level in the range 0-255. For example,
# `set_threshold(SoundEvent.LOUD, 250)` will only trigger if the
# sound is very loud (>= 250).
set_threshold(128)
# Returns a representation of the sound pressure level in the range 0 to 255.
sound_level()

引脚¶

为连接器中的引脚、 V2徽标和V2 扬声器提供数字和模拟输入和输出功能。一些引脚在内部连接到驱动 LED 矩阵和按钮的 I/O。

每个引脚都直接作为microbit模块中的对象提供。这使 API 保持相对平坦，使其非常易于使用：

引脚0

引脚1

…

引脚15

引脚16

警告：P17-P18（含）不可用。

引脚19

引脚20

pin_logo V2

pin_speaker V2

这些引脚中的每一个都是 MicroBitPin 该类的实例，它提供以下 API：

# value can be 0, 1, False, True
pin.write_digital(value)
# returns either 1 or 0
pin.read_digital()
# value is between 0 and 1023
pin.write_analog(value)
# returns an integer between 0 and 1023
pin.read_analog()
# sets the period of the PWM output of the pin in milliseconds
# (see https://en.wikipedia.org/wiki/Pulse-width_modulation)
pin.set_analog_period(int)
# sets the period of the PWM output of the pin in microseconds
# (see https://en.wikipedia.org/wiki/Pulse-width_modulation)
pin.set_analog_period_microseconds(int)
# Only available for touch pins 0, 1, and 2. Returns boolean if the pin
# is touched
pin.is_touched()
# Only available for touch pins 0, 1, 2 and on micro:bit V2 also the logo.
# Sets the touch mode. Value can be either RESISTIVE or CAPACITIVE
pin.set_touch_mode(value)

除了标记为 V2的引脚，它提供以下 API：

pin_logo:

# returns boolean for logo touch pin
pin_logo.is_touched()
# Sets the touch mode. Value can be either RESISTIVE or CAPACITIVE
pin.set_touch_mode(value)

pin_speaker:

同上 MicroBitPin 类，但不包括pin.is_touched().

图片¶

笔记

您并不总是需要自己创建其中之一 - 您可以使用display.image直接访问显示器上显示的图像。display.image 只是Image 的一个实例，因此您可以使用所有相同的方法。

图像API：

# creates an empty 5x5 image
image = Image()
# create an image from a string - each character in the string represents an
# LED - 0 (or space) is off and 9 is maximum brightness. The colon ":"
# indicates the end of a line.
image = Image('90009:09090:00900:09090:90009:')
# create an empty image of given size
image = Image(width, height)
# initialises an Image with the specified width and height. The buffer
# should be an array of length width * height
image = Image(width, height, buffer)

# methods
# returns the image's width (most often 5)
image.width()
# returns the image's height (most often 5)
image.height()
# sets the pixel at the specified position (between 0 and 9). May fail for
# constant images.
image.set_pixel(x, y, value)
# gets the pixel at the specified position (between 0 and 9)
image.get_pixel(x, y)
# returns a new image created by shifting the picture left 'n' times.
image.shift_left(n)
# returns a new image created by shifting the picture right 'n' times.
image.shift_right(n)
# returns a new image created by shifting the picture up 'n' times.
image.shift_up(n)
# returns a new image created by shifting the picture down 'n' times.
image.shift_down(n)
# get a compact string representation of the image
repr(image)
# get a more readable string representation of the image
str(image)

#operators
# returns a new image created by superimposing the two images
image + image
# returns a new image created by multiplying the brightness of each pixel by n
image * n

内置图像

Image.HEART Image.HEART_SMALL Image.HAPPY Image.SMILE Image.SAD Image.CONFUSED Image.ANGRY Image.ASLEEP Image.SURPRISED Image.SILLY Image.FABULOUS Image.MEH Image.YES Image.NO Image.TRIANGLE Image.TRIANGLE_LEFT Image.CHESSBOARD Image.DIAMOND Image.DIAMOND_SMALL Image.SQUARE Image.SQUARE_SMALL Image.RABBIT Image.COW Image.MUSIC_CROTCHET Image.MUSIC_QUAVER Image.MUSIC_QUAVERS Image.PITCHFORK Image.XMAS Image.PACMAN Image.TARGET Image.TSHIRT Image.ROLLERSKATE Image.DUCK Image.HOUSE Image.TORTOISE Image.BUTTERFLY Image.STICKFIGURE Image.GHOST Image.SWORD Image.GIRAFFE Image.SKULL Image.UMBRELLA Image.SNAKE

时钟：

Image.CLOCK1 Image.CLOCK2 Image.CLOCK3 Image.CLOCK4 Image.CLOCK5 Image.CLOCK6 Image.CLOCK7 Image.CLOCK8 Image.CLOCK9 Image.CLOCK10 Image.CLOCK11 Image.CLOCK12

箭头：

Image.ARROW_N Image.ARROW_NE Image.ARROW_E Image.ARROW_SE Image.ARROW_S Image.ARROW_SW Image.ARROW_W Image.ARROW_NW

以下是 Python 图像列表，可用于自动显示动画或手动遍历它们。

Image.ALL_CLOCKS Image.ALL_ARROWS

加速度计¶

加速度计通过accelerometer 对象访问：

# read the X axis of the device. Measured in milli-g.
accelerometer.get_x()
# read the Y axis of the device. Measured in milli-g.
accelerometer.get_y()
# read the Z axis of the device. Measured in milli-g.
accelerometer.get_z()
# get tuple of all three X, Y and Z readings (listed in that order).
accelerometer.get_values()
# return the name of the current gesture.
accelerometer.current_gesture()
# return True or False to indicate if the named gesture is currently active.
accelerometer.is_gesture(name)
# return True or False to indicate if the named gesture was active since the
# last call.
accelerometer.was_gesture(name)
# return a tuple of the gesture history. The most recent is listed last.
accelerometer.get_gestures()

识别的手势是： up, down, left, right, face up, face down, freefall, 3g, 6g, 8g, shake.

罗盘¶

指南针是通过指南针对象访问的：

# calibrate the compass (this is needed to get accurate readings).
compass.calibrate()
# return a numeric indication of degrees offset from "north".
compass.heading()
# return an numeric indication of the strength of magnetic field around
# the micro:bit.
compass.get_field_strength()
# returns True or False to indicate if the compass is calibrated.
compass.is_calibrated()
# resets the compass to a pre-calibration state.
compass.clear_calibration()

I2C总线¶

micro:bit 上有一个 I2C 总线，通过i2c对象公开。它有以下方法：

# read n bytes from device with addr; repeat=True means a stop bit won't
# be sent.
i2c.read(addr, n, repeat=False)
# write buf to device with addr; repeat=True means a stop bit won't be sent.
i2c.write(addr, buf, repeat=False)

声音V2¶

micro:bitV2提供了一组富有表现力的声音。它们可以通过microbit模块访问并使用音频模块播放。

内置声音

Sound.GIGGLE Sound.HAPPY Sound.HELLO Sound.MYSTERIOUS Sound.SAD Sound.SLIDE Sound.SOARING Sound.SPRING Sound.TWINKLE Sound.YAWN

扬声器 V2¶

扬声器默认启用，可以使用 speaker 对象访问。它可以关闭或打开：

# disable the built-in speaker
speaker.off()
# enable the built-in speaker
speaker.on()
# returns True or False to indicate if the speaker is on or off
speaker.is_on()

串口¶

用于 uart与连接到设备 I/O 引脚的串行设备通信：

# set up communication (use pins 0 [TX] and 1 [RX]) with a baud rate of 9600.
uart.init()
# return True or False to indicate if there are incoming characters waiting to
# be read.
uart.any()
# return (read) n incoming characters.
uart.read(n)
# return (read) as much incoming data as possible.
uart.read()
# return (read) all the characters to a newline character is reached.
uart.readline()
# read bytes into the referenced buffer.
uart.readinto(buffer)
# write bytes from the buffer to the connected device.
uart.write(buffer)