pySerial 缓冲区不会刷新 [英] pySerial buffer won't flush

问题描述

我在 Windows 和 Linux 下使用 pySerial 时遇到串行 IO 问题.使用此代码，设备永远不会收到命令并且读取超时:

I'm having a problem with serial IO under both Windows and Linux using pySerial. With this code the device never receives the command and the read times out:

import serial
ser = serial.Serial('/dev/ttyUSB0',9600,timeout=5)
ser.write("get")
ser.flush()
print ser.read()

此代码第一次超时，但后续迭代成功:

This code times out the first time through, but subsequent iterations succeed:

import serial
ser = serial.Serial('/dev/ttyUSB0',9600,timeout=5)
while True:
    ser.write("get")
    ser.flush()
    print ser.read()

谁能告诉我这是怎么回事?我尝试添加对 sync() 的调用，但它不会将串行对象作为参数.

Can anyone tell what's going on? I tried to add a call to sync() but it wouldn't take a serial object as it's argument.

谢谢，罗伯特

推荐答案

在写入和读取之间放置一些延迟例如

Put some delay in between write and read e.g.

import serial
ser = serial.Serial('/dev/ttyUSB0',9600,timeout=5)
ser.flushInput()
ser.flushOutput()
ser.write("get") 

# sleep(1) for 100 millisecond delay
# 100ms dely
sleep(.1)
print ser.read()

这篇关于pySerial 缓冲区不会刷新的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！