我正在使用 Pi Zero 2 和电子纸显示器制作一个小型股票跟踪器。目前我只有一个按钮，当按下循环到下一个股票时，也会用该股票信息更新显示。
这一切都有效，但由于这些显示器并不意味着长时间保持供电，因此我需要在每次显示器刷新后添加一个睡眠呼叫。我使用 gpiozero 添加了一个按钮，在我的 press() 函数的末尾添加了一个睡眠功能，它都工作了......一次。我第一次按下按钮一切顺利，但第二次吐出错误。经过一些试验和错误后，我发现这是导致问题的睡眠呼叫。
我的代码如下：
#!/usr/bin/python
# -*- coding:utf-8 -*-
import sys
import os
picdir = 'pic'
libdir = os.path.join(os.path.dirname(os.path.dirname(os.path.realpath(__file__))), 'lib')
if os.path.exists(libdir):
sys.path.append(libdir)
import logging
from waveshare_epd import epd2in13_V3
import time
from PIL import Image,ImageDraw,ImageFont
import traceback
import yfinance as yf
from gpiozero import Button
import keyboard
logging.basicConfig(level=logging.DEBUG)
button = Button(2)
pageNum = 0
pageMax = 2
def pressed():
print("Pressed")
global pageNum, pageMax
if pageNum < pageMax:
pageNum += 1
elif pageNum >= pageMax:
pageNum = 0
amc = yf.Ticker("AMC")
gme = yf.Ticker("GME")
msft = yf.Ticker("MSFT")
if pageNum == 0:
print("GME selected")
print(pageNum)
stock = "GME"
buy = gme.info['ask']
sell = gme.info['bid']
high = gme.info['dayHigh']
low = gme.info['dayLow']
opening = gme.info['open']
current = gme.info['currentPrice']
elif pageNum == 1:
print("MSFT selected")
print(pageNum)
stock = "MSFT"
buy = msft.info['ask']
sell = msft.info['bid']
high = msft.info['dayHigh']
low = msft.info['dayLow']
opening = msft.info['open']
current = msft.info['currentPrice']
elif pageNum == 2:
print("AMC selected")
print(pageNum)
stock = "AMC"
buy = amc.info['ask']
sell = amc.info['bid']
high = amc.info['dayHigh']
low = amc.info['dayLow']
opening = amc.info['open']
current = amc.info['currentPrice']
buyR = round(buy, 2)
sellR = round(sell, 2)
highR = round(high, 2)
lowR = round(low, 2)
openingR = round(opening, 2)
currentR = round(current, 2)
# Blank out rectangles
draw.rectangle((2, 2, 125, 33), fill = 255)
draw.rectangle((28, 37, 123, 90), fill = 255)
draw.rectangle((151, 37, 247, 90), fill = 255)
draw.rectangle((142, 94, 247, 119), fill = 255)
draw.text((4, 0), str(stock), font = fnt_large, fill = 0)
draw.text((28, 40), str(highR), font = fnt_small, fill = 0)
draw.text((28, 66), str(lowR), font = fnt_small, fill = 0)
draw.text((151, 40), str(buyR), font = fnt_small, fill = 0)
draw.text((151, 66), str(sellR), font = fnt_small, fill = 0)
draw.text((142, 93), str(currentR), font = fnt_med, fill = 0)
epd.displayPartial(epd.getbuffer(image)) # Refresh the prices
logging.info("Sleep from pressed()")
epd.sleep()
button.when_pressed = pressed
try:
logging.info("init and Clear")
epd = epd2in13_V3.EPD()
epd.init()
# epd.Clear(0xFF)
fnt_small = ImageFont.truetype(os.path.join(picdir, 'DejaVuSans-Bold.ttf'), 20)
fnt_med = ImageFont.truetype(os.path.join(picdir, 'DejaVuSans-Bold.ttf'), 24)
fnt_large = ImageFont.truetype(os.path.join(picdir, 'DejaVuSans-Bold.ttf'), 32)
logging.info("New image")
image = Image.new('1', (epd.height, epd.width), 255) # 255 = w BG, 0 = black BG
draw = ImageDraw.Draw(image)
epd.displayPartBaseImage(epd.getbuffer(image)) # Refresh the display
# Draw the table
draw.line([(0,0),(249,0)], fill = 0,width = 1)
draw.line([(249,0),(249,121)], fill = 0,width = 1)
draw.line([(0,121),(249,121)], fill = 0,width = 1)
draw.line([(0,0),(0,121)], fill = 0,width = 1)
draw.line([(0,35),(250,35)], fill = 0,width = 1)
draw.line([(0,92),(250,92)], fill = 0,width = 1)
draw.line([(125,35),(125,92)], fill = 0,width = 1)
draw.text((4, 40), 'H:', font = fnt_small, fill = 0)
draw.text((4, 66), 'L:', font = fnt_small, fill = 0)
draw.text((129, 40), 'B:', font = fnt_small, fill = 0)
draw.text((129, 66), 'S:', font = fnt_small, fill = 0)
draw.text((6, 93), 'CURRENT:', font = fnt_med, fill = 0)
epd.display(epd.getbuffer(image))
while True:
keyboard.wait('q')
keyboard.send('ctrl+6')
logging.info("Sleep mode")
epd.sleep()
except IOError as e:
logging.info(e)
except KeyboardInterrupt:
logging.info("ctrl + c:")
epd2in13_V3.epdconfig.module_exit()
exit
第二次按下按钮时生成的错误代码是：
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/gpiozero/pins/rpigpio.py", line 223, in _call_when_changed
super(RPiGPIOPin, self)._call_when_changed()
File "/usr/lib/python3/dist-packages/gpiozero/pins/local.py", line 130, in _call_when_changed
self.state if state is None else state)
File "/usr/lib/python3/dist-packages/gpiozero/pins/pi.py", line 298, in _call_when_changed
method(ticks, state)
File "/usr/lib/python3/dist-packages/gpiozero/input_devices.py", line 182, in _pin_changed
self._fire_events(ticks, bool(self._state_to_value(state)))
File "/usr/lib/python3/dist-packages/gpiozero/mixins.py", line 401, in _fire_events
self._fire_activated()
File "/usr/lib/python3/dist-packages/gpiozero/mixins.py", line 447, in _fire_activated
super(HoldMixin, self)._fire_activated()
File "/usr/lib/python3/dist-packages/gpiozero/mixins.py", line 364, in _fire_activated
self.when_activated()
File "1.py", line 89, in pressed
epd.displayPartial(epd.getbuffer(image)) # Refresh the prices
File "/home/berry/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13_V3.py", line 311, in displayPa rtial
epdconfig.digital_write(self.reset_pin, 0)
File "/home/berry/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 53, in digital_writ e
self.GPIO.output(pin, value)
RuntimeError: The GPIO channel has not been set up as an OUTPUT
我尝试了几种不同的方法来尝试使其正常工作，但是完全没有想法，似乎无论我把它放在哪里，睡眠线在第二次被调用时总是出错。