这是针对 ESP8266 版的快速指南，请大家注意与 pyboard 版的区别。简单介绍一组有关 ESP8266 开发板下使用 MicroPython 开发的范例程序。

machine 和频率控制

import machine

machine.freq() # get the current frequency of the CPU
machine.freq(160000000) # set the CPU frequency to 160 MHz

ESP模块

import esp

esp.osdebug(None) # turn off vendor O/S debugging messages
esp.osdebug(0) # redirect vendor O/S debugging messages to UART(0)

网络

import network

wlan = network.WLAN(network.STA_IF) # create station interface
wlan.active(True) # activate the interface
wlan.scan() # scan for access points
wlan.isconnected() # check if the station is connected to an AP
wlan.connect('essid', 'password') # connect to an AP
wlan.config('mac') # get the interface's MAC adddress
wlan.ifconfig() # get the interface's IP/netmask/gw/DNS addresses

ap = network.WLAN(network.AP_IF) # create access-point interface
ap.active(True) # activate the interface
ap.config(essid='ESP-AP') # set the ESSID of the access point

一个用于连接到你的本地 WiFi 的函数:

def do_connect():
import network
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
if not wlan.isconnected():
print('connecting to network...')
wlan.connect('essid', 'password')
while not wlan.isconnected():
pass
print('network config:', wlan.ifconfig())
网络连接后，就可以创建和使用 TCP/UDP 了。

GPIO

from machine import Pin

p0 = Pin(0, Pin.OUT) # create output pin on GPIO0
p0.high() # set pin to high
p0.low() # set pin to low
p0.value(1) # set pin to high

p2 = Pin(2, Pin.IN) # create input pin on GPIO2
print(p2.value()) # get value, 0 or 1

p4 = Pin(4, Pin.IN, Pin.PULL_UP) # enable internal pull-up resistor
p5 = Pin(5, Pin.OUT, value=1) # set pin high on creation

定时器

from machine import Timer

tim = Timer(-1)
tim.init(period=5000, mode=Timer.ONE_SHOT, callback=lambda t:print(1))
tim.init(period=2000, mode=Timer.PERIODIC, callback=lambda t:print(2))

延时

import time

time.sleep(1) # sleep for 1 second
time.sleep_ms(500) # sleep for 500 milliseconds
time.sleep_us(10) # sleep for 10 microseconds
start = time.ticks_ms() # get millisecond counter
delta = time.ticks_diff(start, time.ticks_ms()) # compute time difference

PWM

from machine import Pin, PWM

pwm0 = PWM(Pin(0)) # create PWM object from a pin
pwm0.freq() # get current frequency
pwm0.freq(1000) # set frequency
pwm0.duty() # get current duty cycle
pwm0.duty(200) # set duty cycle
pwm0.deinit() # turn off PWM on the pin

pwm2 = PWM(Pin(2), freq=500, duty=512) # create and configure in one go

ADC

from machine import ADC

adc = ADC(0) # create ADC object on ADC pin
adc.read() # read value, 0-1024

软件 SPI

SPI 有两种驱动。一种是软件方式 (bit-banging)，可以使用任何 pins:

from machine import Pin, SPI

# construct an SPI bus on the given pins
# polarity is the idle state of SCK
# phase=0 means sample on the first edge of SCK, phase=1 means the second
spi = SPI(-1, baudrate=100000, polarity=1, phase=0, sck=Pin(0), mosi=Pin(2), miso=Pin(4))

spi.init(baudrate=200000) # set the baudrate

spi.read(10) # read 10 bytes on MISO
spi.read(10, 0xff) # read 10 bytes while outputing 0xff on MOSI

buf = bytearray(50) # create a buffer
spi.readinto(buf) # read into the given buffer (reads 50 bytes in this case)
spi.readinto(buf, 0xff) # read into the given buffer and output 0xff on MOSI

spi.write(b'12345') # write 5 bytes on MOSI

buf = bytearray(4) # create a buffer
spi.write_readinto(b'1234', buf) # write to MOSI and read from MISO into the buffer
spi.write_readinto(buf, buf) # write buf to MOSI and read MISO back into buf

硬件 SPI

硬件 SPI 速度更快 (最高 80Mhz)，但是只能使用下面的 pins: MISO – GPIO12, MOSI – GPIO13, 以及 SCK – GPIO14。它的用法和上面的软件SPI相同，除了pin参数:

from machine import Pin, SPI

hspi = SPI(1, baudrate=80000000, polarity=0, phase=0)
(SPI(0) 仅用于内部的 FlashROM。)

I2C

from machine import Pin, I2C

# construct an I2C bus
i2c = I2C(scl=Pin(5), sda=Pin(4), freq=100000)

i2c.readfrom(0x3a, 4) # read 4 bytes from slave device with address 0x3a
i2c.writeto(0x3a, '12') # write '12' to slave device with address 0x3a

buf = bytearray(10) # create a buffer with 10 bytes
i2c.writeto(0x3a, buf) # write the given buffer to the slave

休眠

import machine

# configure RTC.ALARM0 to be able to wake the device
rtc = machine.RTC()
rtc.irq(trigger=rtc.ALARM0, wake=machine.DEEPSLEEP)

# check if the device woke from a deep sleep
if machine.reset_cause() == machine.DEEPSLEEP_RESET:
print('woke from a deep sleep')

# set RTC.ALARM0 to fire after 10 seconds (waking the device)
rtc.alarm(rtc.ALARM0, 10000)

# put the device to sleep
machine.deepsleep()

onewire 总线

from machine import Pin
import onewire

ow = onewire.OneWire(Pin(12)) # create a OneWire bus on GPIO12
ow.scan() # return a list of devices on the bus
ow.reset() # reset the bus
ow.readbyte() # read a byte
ow.read(5) # read 5 bytes
ow.writebyte(0x12) # write a byte on the bus
ow.write('123') # write bytes on the bus
ow.select_rom(b'12345678') # select a specific device by its ROM code

驱动 DS18B20

import time
ds = onewire.DS18B20(ow)
roms = ds.scan()
ds.convert_temp()
time.sleep_ms(750)
for rom in roms:
print(ds.read_temp(rom))

网络

import network

wlan = network.WLAN(network.STA_IF) # create station interface
wlan.active(True) # activate the interface
wlan.scan() # scan for access points
wlan.isconnected() # check if the station is connected to an AP
wlan.connect('essid', 'password') # connect to an AP
wlan.config('mac') # get the interface's MAC adddress
wlan.ifconfig() # get the interface's IP/netmask/gw/DNS addresses

ap = network.WLAN(network.AP_IF) # create access-point interface
ap.active(True) # activate the interface
ap.config(essid='ESP-AP') # set the ESSID of the access point

def do_connect():
import network
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
if not wlan.isconnected():
print('connecting to network...')
wlan.connect('essid', 'password')
while not wlan.isconnected():
pass
print('network config:', wlan.ifconfig())

NeoPixel 驱动

from machine import Pin
from neopixel import NeoPixel

pin = Pin(0, Pin.OUT) # set GPIO0 to output to drive NeoPixels
np = NeoPixel(pin, 8) # create NeoPixel driver on GPIO0 for 8 pixels
np[0] = (255, 255, 255) # set the first pixel to white
np.write() # write data to all pixels
r, g, b = np[0] # get first pixel colour

底层驱动

import esp
esp.neopixel_write(pin, grb_buf, is800khz)

APA102驱动

from machine import Pin
from apa102 import APA102

clock = Pin(14, Pin.OUT) # set GPIO14 to output to drive the clock
data = Pin(13, Pin.OUT) # set GPIO13 to output to drive the data
apa = APA102(clock, data, 8) # create APA102 driver on the clock and the data pin for 8 pixels
apa[0] = (255, 255, 255, 31) # set the first pixel to white with a maximum brightness of 31
apa.write() # write data to all pixels
r, g, b, brightness = apa[0] # get first pixel colour

底层驱动

import esp
esp.apa102_write(clock_pin, data_pin, rgbi_buf)

webrepl

import webrepl
webrepl.start()
webrepl.stop()

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