使用一个Arduino Duemilanove和Cutedigi RS-232接口，RS-232通讯 [英] RS-232 communication using an Arduino Duemilanove and the Cutedigi RS-232 interface

问题描述

我有一些麻烦我的Arduino单片机读取 RS-232信号 。我的项目需要我读正由一个空气质量监测输出的数据。

I'm having some trouble getting my Arduino microcontroller to read RS-232 signals. My project requires me to read data that is being outputted by an air quality monitor.

我的组件：

• 的Arduino Duemilanove


• Cutedigi RS-232接口

• Arduino Duemilanove
• Cutedigi RS-232 interface

要测试是否串行通信工作正常，我发现Arduino的网站上的一些例如code。这是我运行的确切code：

To test if the serial communications is working properly, I found some example code on the Arduino website. This is the exact code that I am running:

//Created August 23 2006
//Heather Dewey-Hagborg
//http://www.arduino.cc

#include <ctype.h>

#define bit9600Delay 84
#define halfBit9600Delay 42
#define bit4800Delay 188
#define halfBit4800Delay 94

byte rx = 0;
byte tx = 1;
byte SWval;

void setup() {
    pinMode(rx,INPUT);
    pinMode(tx,OUTPUT);
    digitalWrite(tx,HIGH);
    digitalWrite(13,HIGH); //turn on debugging LED
    SWprint('h');  //debugging hello
    SWprint('i');
    SWprint(10); //carriage return
}

void SWprint(int data)
{
    byte mask;
    //startbit
    digitalWrite(tx,LOW);
    delayMicroseconds(bit9600Delay);
    for (mask = 0x01; mask>0; mask <<= 1) {
        if (data & mask){ // choose bit
            digitalWrite(tx,HIGH); // send 1
        }
        else{
            digitalWrite(tx,LOW); // send 0
        }
        delayMicroseconds(bit9600Delay);
    }
    //stop bit
    digitalWrite(tx, HIGH);
    delayMicroseconds(bit9600Delay);
}

int SWread()
{
    byte val = 0;
    while (digitalRead(rx));
    //wait for start bit
    if (digitalRead(rx) == LOW) {
        delayMicroseconds(halfBit9600Delay);
        for (int offset = 0; offset < 8; offset++) {
            delayMicroseconds(bit9600Delay);
            val |= digitalRead(rx) << offset;
        }
        //wait for stop bit + extra
        delayMicroseconds(bit9600Delay);
        delayMicroseconds(bit9600Delay);
        return val;
    }
}

void loop()
{
    SWval = SWread();
    SWprint(toupper(SWval));
}

我改变RX和TX引脚分别为0和1，因为这些是在Cutedigi的RS-232芯片使用的管脚。现在，当我打开一个终端窗口和类型的字符，我得到乱码的符号和字母。（是这样的：¾_ò_òòËÌßÌËßÌÊÌòyofyofsæóÙöÇAEUæ）

根据该示例code网站上，如果键入 ABCDEFG ，终端窗口应该显示 ABCDEFG

According to the example code website, if I type abcdefg, the terminal window should display ABCDEFG.

为什么会变成这样？我已经设置波特率为9600，如草图规定，但我仍然得到的问题。重置Arduino的似乎并没有任何帮助 - 我仍然得到乱码

Why would this be the case? I have set the baud rate to 9600, as specified in the sketch, but I'm still getting issues. Resetting the Arduino doesn't seem to help either - I still get garbled text.

推荐答案

我想出什么问题了。

原来，我是想两个DCE设备连接在一起，这意味着空调制解调器适配器是需要交换电缆上的TX / RX引脚。 previously，我用一个简单的对接转换器，但是这是什么导致我的问题。

It turns out that I was trying to connect two DCE devices together, which means that a null modem adapter was necessary to swap the TX/RX pins on the cable. Previously, I was using a simple gender changer, but this is what was causing my problems.

尝试获得，如果你有这样的问题零调制解调器适配器。

Try getting a null modem adapter if you're having problems like this.

这篇关于使用一个Arduino Duemilanove和Cutedigi RS-232接口，RS-232通讯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！