一、關(guān)于雙色 LED
紅綠雙色LED，一般紅色代表忙碌，綠色代表準(zhǔn)備。
雙色LED，實(shí)際上是有兩個(gè)LED燈，各兩個(gè)腳，共用一個(gè)腳，就變成三個(gè)腳。如果共陽，稱為共陽型，共陰，稱為共陰型。
我們用的，是共陰型。
如圖，引腳處的-代表GND，S代表高電平。
二、關(guān)于通道
GPIO number并不是通道，GPIO number所對(duì)應(yīng)的1-40的引腳序號(hào)，才是通道。
三、一個(gè)跑馬燈實(shí)例
import RPi.GPIO as GPIO
import time
pins = {'pin_R':11, 'pin_G':12}? # pins is a dict
sleep_time =0.5
GPIO.setmode(GPIO.BOARD)? ? ? # Numbers GPIOs by physical location
for i in pins:
GPIO.setup(pins[i], GPIO.OUT)? # Set pins' mode is output
GPIO.output(pins[i], GPIO.LOW) # Set pins to low(0V) to off led
print("i is ",i,pins[i])
def loop():
while True:
? ? ? ? ? ? GPIO.output(pins['pin_R'], GPIO.HIGH)? # Set pins to high(+3.3V) to on led
? ? ? ? ? ? print(pins['pin_R']," Red Led is On...")
? ? ? ? ? ? time.sleep(sleep_time)
? ? ? ? ? ? GPIO.output(pins['pin_R'], GPIO.LOW)
? ? ? ? ? ? print(pins['pin_R']," Red Led is off...")
? ? ? ? ? ? time.sleep(sleep_time)
? ? ? ? ? ? GPIO.output(pins['pin_G'], GPIO.HIGH)
? ? ? ? ? ? print(pins['pin_G']," Green Led is On...")
? ? ? ? ? ? time.sleep(sleep_time)
? ? ? ? ? ? GPIO.output(pins['pin_G'], GPIO.LOW)
? ? ? ? ? ? print(pins['pin_G']," Green Led is off...")
? ? ? ? ? ? time.sleep(sleep_time)
def destroy():
for i in pins:
GPIO.output(pins[i], GPIO.LOW)? ? # Turn off all leds
GPIO.cleanup()
if __name__ == "__main__":
try:
loop()
except KeyboardInterrupt:
destroy()
