我在Raspberry Pi上运行以下python脚本:
http://www.skpang.co.uk/dl/rfid.py
我已经将脚本修改到最后以访问GPIO引脚15并打开和关闭它。这是我底部的代码:
def example():
rfid = SL030()
fw = rfid.get_firmware()
print("RFID reader firmware:" + fw)
print()
GPIO.setmode(GPIO.BOARD)
GPIO.setup(15, GPIO.OUT)
GPIO.output(15,True)
while True:
rfid.wait_tag()
print("card present")
if rfid.select_mifare():
type = rfid.get_type()
print("type:" + rfid.get_typename(type))
id = rfid.get_uidstr()
try:
user = cards[id]
print(user)
#os.system("aplay " + user)
except KeyError:
print("Unknown card:" + id)
rfid.wait_notag()
print("card removed")
print()
我面临的问题是虽然它操作引脚15,但脚本会因以下错误而停止:
Traceback (most recent call last):
File "./rfid.py", line 212, in <module>
example()
File "./rfid.py", line 182, in example
rfid.wait_tag()
File "./rfid.py", line 45, in wait_tag
while not self.tag_present():
File "./rfid.py", line 40, in tag_present
return GPIO.input(CFG_TAG_DETECT) == False
RPi.GPIO.InvalidChannelException: The channel sent is invalid on a Raspberry Pi
任何想法可能出错?
由于
的更新 的
如果我把GPIO代码放在def示例()之下:并且在rfid = SL030()之上,如下所示,那么它似乎没有错误地工作:
def example():
GPIO.setmode(GPIO.BOARD)
GPIO.setup(15, GPIO.OUT)
GPIO.output(15,True)
rfid = SL030()
* 更新 - 解决方案 *
感谢André,我改变了:
GPIO.setmode(GPIO.BOARD)
于: GPIO.setmode(GPIO.BCM)
然后更改端口以匹配BCM端口,如下所示:
GPIO.setup(22, GPIO.OUT)
GPIO.output(22,True)