请教一下有关程序的问题

[f6sw]

你好，可否帮我看看这程序哪里有错误为啥输出的了time_start却输出不了duration

import time, pyb
from pyb import Pin, ExtInt

counter=0

def count(line):
    global counter
    counter += 1
    if counter == 1:
       time_start = pyb.millis()
       print(time_start)
    if counter == 2:
       duration = pyb.elapsed_millis(time_start)
       print(duration)
       counter = 0
ext = ExtInt(Pin('P5'), ExtInt.IRQ_RISING_FALLING, Pin.PULL_UP, count)
while True:
    pass

[kidswong999]

你这个程序是做什么的

[f6sw]

就是检测到上升沿开始计时，检测到下降沿停止计时，得到高电平的时间

[kidswong999]

下面的代码，把P5置高，再断开就可以看到效果。

import time, pyb
from pyb import Pin, ExtInt

time_start = 0
duration = 0
value = 0
def pulse_in(line):
    global time_start
    global time_delta
    global value
    value = Pin('P5').value()
    if value:
        time_start = pyb.millis()
        print("time start:",time_start)
    else:
        duration = pyb.elapsed_millis(time_start)
        print('duration: ', duration)

ext = ExtInt(Pin('P5'), ExtInt.IRQ_RISING_FALLING, Pin.PULL_DOWN, pulse_in)

while True:
    pass

[f6sw]

谢谢。。解决了哈哈