首页 > 解决方案 > RPi.GPIO 中断调用函数的时间不够长

问题描述

所以我正在尝试设计一个 LCD 屏幕来拥有一个菜单和一堆不同的功能,它应该有 4 个按钮。一个选择、一个菜单和一个向上和向下。现在我只是想在菜单按钮上工作。我希望它始终显示时钟,除非按下菜单按钮。但是当我按下按钮时,它不会在屏幕上停留 5 秒钟。我也不知道为什么它也不会。我已经查看了 RPi 中断并跟踪了它,但它仍然不会留下来。“嗨”出现不到半秒。我还在使用树莓派间谍的 LCD 库,如果需要,我可以链接它。我所做的唯一一件事就是修改一些计时内容以匹配我的显示器,并添加了一次向四行中的任何一行添加文本的功能,因为我有一个 20x4 显示器。

这是代码:

#!usr/bin/python3
import RPi.GPIO as GPIO
import time
import sys
sys.path.append('/home/pi/Downloads')
import lcd

GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD)
#GPIO.setup(33, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(11, GPIO.IN, pull_up_down=GPIO.PUD_UP)
#GPIO.setup(13, GPIO.IN, pull_up_down=GPIO.PUD_UP)
#GPIO.setup(15, GPIO.IN, pull_up_down=GPIO.PUD_UP)


lcd.lcd_init()

def start():
    for x in range(0,8):
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}>----TestOS----<{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}<>---TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-<>--TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}--<>-TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}---<>TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}----<TestOS>----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS<>---{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS-<>--{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS--<>-{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS---<>{]", 1)
        time.sleep(0.1)


    lcd.lcd_init()

    for x in range(0,120):
        lcd.lcd_byte(0xFF,True)

    time.sleep(5)
    lcd.lcd_init()


def Menu():
    lcd.lcd_init()
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("hi", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string("hi", 1)
    time.sleep(5)

def clock():
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%I:%M %p          |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_3, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%a, %b %d, %Y |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_4, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    time.sleep(1)
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%I %M %p          |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_3, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%a, %b %d, %Y |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_4, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    time.sleep(1)

GPIO.add_event_detect(11, GPIO.FALLING, callback=Menu, bouncetime=100)

start()
try:
    while True:
        clock()

finally:
    lcd.lcd_init()
    lcd.GPIO.cleanup()
    GPIO.cleanup()

PS:lcd.lcd_init 加倍清除屏幕,这就是我这么称呼它的原因。

标签: pythonraspberry-picharactergpiolcd

解决方案


您的方法 clock() 在无限循环中运行,始终会随时间覆盖显示的文本。

当 Menu() 函数运行时,您必须停止 clock() 方法。

我按下了全局变量菜单:

#!usr/bin/python3
import RPi.GPIO as GPIO
import time
import sys
sys.path.append('/home/pi/Downloads')
import lcd

GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD)
#GPIO.setup(33, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(11, GPIO.IN, pull_up_down=GPIO.PUD_UP)
#GPIO.setup(13, GPIO.IN, pull_up_down=GPIO.PUD_UP)
#GPIO.setup(15, GPIO.IN, pull_up_down=GPIO.PUD_UP)

menupressed = False

lcd.lcd_init()

def start():
    for x in range(0,8):
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}>----TestOS----<{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}<>---TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-<>--TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}--<>-TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}---<>TestOS-----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}----<TestOS>----{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS<>---{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS-<>--{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS--<>-{]", 1)
        time.sleep(0.1)
        lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
        lcd.lcd_string("[}-----TestOS---<>{]", 1)
        time.sleep(0.1)


    lcd.lcd_init()

    for x in range(0,120):
        lcd.lcd_byte(0xFF,True)

    time.sleep(5)
    lcd.lcd_init()


def Menu():
    global menupressed
    menupressed = True
    lcd.lcd_init()
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("hi", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string("hi", 1)
    time.sleep(5)
    menupressed = False

def clock():
    if(menupressed):
         return #when menu button is pressed, return - dont show nothing on display
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%I:%M %p          |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_3, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%a, %b %d, %Y |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_4, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    time.sleep(1)
    lcd.lcd_byte(lcd.LCD_LINE_1, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    lcd.lcd_byte(lcd.LCD_LINE_2, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%I %M %p          |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_3, lcd.LCD_CMD)
    lcd.lcd_string(time.strftime("|%a, %b %d, %Y |"), 1)
    lcd.lcd_byte(lcd.LCD_LINE_4, lcd.LCD_CMD)
    lcd.lcd_string("+------------------+", 1)
    time.sleep(1)

GPIO.add_event_detect(11, GPIO.FALLING, callback=Menu, bouncetime=100)

start()
try:
    while True:
        clock()

finally:
    lcd.lcd_init()
    lcd.GPIO.cleanup()
    GPIO.cleanup()

希望对您有所帮助


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