MicroPython_ESP8266_IoT——第三回 纸上得来（学习手册知识点）

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

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

 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())

 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(time.ticks_ms(), start) # compute time difference

 from machine import Pin
 ​
 p0 = Pin(0, Pin.OUT)    # create output pin on GPIO0
 p0.on()                 # set pin to "on" (high) level
 p0.off()                # set pin to "off" (low) level
 p0.value(1)             # set pin to on/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

 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

 import time, math, machine
 ​
 led = machine.PWM(machine.Pin(2), freq=1000)
 ​
 def pulse(l, t):
     for i in range(400):
         l.duty(int(math.sin(i / 200 * math.pi) * 500 + 523))
         time.sleep_ms(t)
         
 def fading():
     for i in range(50):
         pulse(led, 5)