pySerial: port 仅在我开机后第一次使用时才有效
•浏览 1
pySerial: port only works the first I use it after I power it on
我无法使用 pySerial 读取任意端口。我只能在端口打开后没有被任何程序使用时读取端口。否则,我可以打开端口,但 ser.inWaiting() 返回 0,告诉我端口缓冲区中没有数据。实际上,我可以在端口监视器中看到数据,那么为什么 pySerial 没有数据呢?我正在使用 os x 10.9.5.、python 2.7.8 和 pySerial 2.7
代码如下:
def usb():
ser = serial.Serial('/dev/tty.usbmodem422651', 115200)
try:
while True:
print ser.read(1000)
except KeyboardInterrupt:
ser.close()
exit
if __name__ =="__main__":
testUSB()
while True:
print ser.read(1000)
if ser.inWaiting:
ser.read(len(ser.inWaiting()))
import serial
def my_usb():
s_handle = serial.Serial('/dev/tty.usbmodem422651', 115200)
# or any other end condition
while True:
try:
if s_handle.inWaiting():
print s_handle.read(s_handle.inWaiting())
except KeyboardInterrupt:
print"exiting...."
finally:
s_handle.close()
if __name__ =="__main__":
my_usb()
感谢您的帮助!
你需要了解串行是如何工作的。
如果你已经打开了某个终端并读取了数据,那么它的串口输入缓冲区现在是空的。
def usb():
ser = serial.Serial('/dev/tty.usbmodem422651', 115200)
try:
while True:
print ser.read(1000)
except KeyboardInterrupt:
ser.close()
exit
if __name__ =="__main__":
testUSB()
while True:
print ser.read(1000)
if ser.inWaiting:
ser.read(len(ser.inWaiting()))
import serial
def my_usb():
s_handle = serial.Serial('/dev/tty.usbmodem422651', 115200)
# or any other end condition
while True:
try:
if s_handle.inWaiting():
print s_handle.read(s_handle.inWaiting())
except KeyboardInterrupt:
print"exiting...."
finally:
s_handle.close()
if __name__ =="__main__":
my_usb()
这不是一个好习惯,您可以使用 inWating 尝试以下操作:
def usb():
ser = serial.Serial('/dev/tty.usbmodem422651', 115200)
try:
while True:
print ser.read(1000)
except KeyboardInterrupt:
ser.close()
exit
if __name__ =="__main__":
testUSB()
while True:
print ser.read(1000)
if ser.inWaiting:
ser.read(len(ser.inWaiting()))
import serial
def my_usb():
s_handle = serial.Serial('/dev/tty.usbmodem422651', 115200)
# or any other end condition
while True:
try:
if s_handle.inWaiting():
print s_handle.read(s_handle.inWaiting())
except KeyboardInterrupt:
print"exiting...."
finally:
s_handle.close()
if __name__ =="__main__":
my_usb()
您无法从 2 个不同的应用程序或软件打开端口。
一个好的代码应该是这样的:
def usb():
ser = serial.Serial('/dev/tty.usbmodem422651', 115200)
try:
while True:
print ser.read(1000)
except KeyboardInterrupt:
ser.close()
exit
if __name__ =="__main__":
testUSB()
while True:
print ser.read(1000)
if ser.inWaiting:
ser.read(len(ser.inWaiting()))
import serial
def my_usb():
s_handle = serial.Serial('/dev/tty.usbmodem422651', 115200)
# or any other end condition
while True:
try:
if s_handle.inWaiting():
print s_handle.read(s_handle.inWaiting())
except KeyboardInterrupt:
print"exiting...."
finally:
s_handle.close()
if __name__ =="__main__":
my_usb()