提问者:小点点

Python Pyserial 同时从多个串行端口读取数据 [重复]


我正在尝试使用Python2.7和PySerial同时读取多个串行端口
功能应为:

  1. 在主程序中,我获取所有打开的串行端口,打开它们并将串行对象附加到串行对象
  2. 我想在一个子进程中读取每个串行端口数据以进行并行化

最大的问题是:如何将串口对象传递给子进程?
或者:
是否存在另一种(也许更好)的解决方案?(也许是这个:如何将双绞串口应用于我的问题?

我想我不完全清楚我想要实现什么。
我想同时读出2个或更多串行端口。由于超时和读出时间,不可能在一个进程中同时读出它们。
以下方法

ser1 = serial.Serial(port="COM1",baudrate=9600)
ser2 = serial.Serial(port="COM2",baudrate=9600)

ser1.write('command for reading out device 1')
output1 = ser1.readline()

ser2.write('command for reading out device 2')
# now you have to wait at least 100ms for device 2 to respond
output2 = ser2.readline()

不能满足我的需要。

另一种方法是并行化子进程中的串行读取。

import serial   # serial communication
from subprocess import Popen, PIPE

ports = ["COM1", "COM2"]
for port in ports:
    ser = serial.Serial()
    ser.port=port
    ser.baudrate=9600
    # set parity and ...

    serialobjects.append(ser)

# call subprocess
# pass the serial object to subprocess
# read out serial port


# HOW TO PASS SERIAL OBJECT HERE to stdin
p1 = Popen(['python', './ReadCOM.py'], stdin=PIPE, stdout=PIPE, stderr=PIPE) # read COM1 permanently
p2 = Popen(['python', './ReadCOM.py'], stdin=PIPE, stdout=PIPE, stderr=PIPE) # read COM2 permanently

for i in range(10):
    print "received from COM1: %s" % p1.stdout.readline() # print output from ReadCOM.py for COM1
    print "received from COM2: %s" % p2.stdout.readline() # print output from ReadCOM.py for COM2
import sys

while True:  # The program never ends... will be killed when master is over.
    # sys.stdin.readline()

    ser.write('serial command here\n') # send command to serial port
    output = ser.readline() # read output

    sys.stdout.write(output) # write output to stdout
    sys.stdout.flush()

提前感谢!


共1个答案

匿名用户

首先更改< code>ReadCOM.py以接收参数

import sys
import serial

ser = serial.Serial(port=sys.argv[1],baudrate=int(sys.argv[2]))
while True:  # The program never ends... will be killed when master is over.
    # sys.stdin.readline()

    ser.write('serial command here\n') # send command to serial port
    output = ser.readline() # read output

    sys.stdout.write(output) # write output to stdout
    sys.stdout.flush()

在< code>main.py中传递它之后:

from subprocess import Popen, PIPE

# call subprocess
# pass the serial object to subprocess
# read out serial port


# HOW TO PASS SERIAL OBJECT HERE to stdin
p1 = Popen(['python', './ReadCOM.py', "COM1", "9600"], stdin=PIPE, stdout=PIPE, stderr=PIPE) # read COM1 permanently
p2 = Popen(['python', './ReadCOM.py', "COM2", "9600"], stdin=PIPE, stdout=PIPE, stderr=PIPE) # read COM2 permanently

for i in range(10):
    print "received from COM1: %s" % p1.stdout.readline() # print output from ReadCOM.py for COM1
    print "received from COM2: %s" % p2.stdout.readline() # print output from ReadCOM.py for COM2