blocks|key|3340421|text|你想要做的事情可以(几乎)通过替换|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3340422|Serial.print(printByte);
for(int+i=0;+i<=sizeof(printByte);i%2B%2B){
+++printByte[i]=0;
}|code-block|syntax|javascript|3340423|使用|3340424|Serial.print(printByte);

for(int+i=0;+i<=sizeof(printByte);i%2B%2B){
+++if+(0+==+printByte[i])
+++++++break;
+++printf("%2502x",+printByte[i]);
}
printf("\n");+//+Newline+after+output

if+(0+==+strpos(printByte,+"QUIT"))
{
++++//+The+cycle+ends.
}

for(int+i=0;+i<=sizeof(printByte);i%2B%2B){
+++printByte[i]=0;
}|3340425|UPDATE：Serial.print()命令是输出0xFF.：我不知道您想要修改输出Arduino端。这一点，我不知道如何实现，需要修改Serial包的源代码。将有一个"+0x+%2502x“或"0x02X”在那里的某处，0x必须被删除。|offset|length|style|BOLD|CODE|3340426|关于读取序列的结尾，您可以输出一个double+\n。然后，如果读取字节为\n而pos为0，这将意味着Arduino编写了空行，而序列已经停止。|3340427|或者，您可以使用几乎任何序列作为终止符:在上面的代码中，我添加了字符串“退出”的检查。|3340428|entityMap^0|0|0|0|0|0|6|1X|6|0|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Y|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Z|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|11|8|@$M|12|N|13|O|P]|$M|14|N|15|O|Q]]|9|@]|A|$]]|$1|R|3|S|5|6|7|16|8|@]|9|@]|A|$]]|$1|T|3|U|5|6|7|17|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|W|$]]

What you want to do can (almost) be accomplished by replacing

<pre><code>Serial.print(printByte);
for(int i=0; i&lt;=sizeof(printByte);i++){
 printByte[i]=0;
}
</code></pre>

with

<pre><code>Serial.print(printByte);

for(int i=0; i&lt;=sizeof(printByte);i++){
 if (0 == printByte[i])
 break;
 printf("%02x", printByte[i]);
}
printf("\n"); // Newline after output

if (0 == strpos(printByte, "QUIT"))
{
 // The cycle ends.
}

for(int i=0; i&lt;=sizeof(printByte);i++){
 printByte[i]=0;
}
</code></pre>

UPDATE: The Serial.print() command is the one outputting 0xFF...: I had not understood that you wanted to modify the output Arduino side. That, I do not know how to implement, would require modifying the sources of the <code>Serial</code> package. There will be a "0x%02x" or "0x02X" in there somewhere from which the 0x has to be removed.

Regarding the end of a sequence of reads, you might output a double \n. Then, if the read byte is \n and pos is 0, this will mean that the Arduino has written an empty line and the sequence has stopped.

Or you might use almost any sequence as a terminator: in the code above I've added a check for the string "QUIT".

blocks|key|4222117|text|您的第一个问题是如何知道什么时候停止读取，如果您不使用'\n‘终止数据包/命令/任何东西。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4222118|答案是，您必须建立某种方法来了解协议中的读入量。串行通信中没有任何固有的内容可以告诉您序列何时结束。只是一个字节流。|4222119|像\n这样的分隔符是一种常见的方法(如果你看到你读过分隔符，就停止)|unordered-list-item|4222120|固定长度的数据包(读取多个字节，然后停止)|4222121|包含“长度”字段的数据包(读取长度字段，然后使用它来决定要读取的字节数)|4222122|4222123|4222124|如果你的协议没有做任何这些事情，你的读者就不可能知道什么时候停止。哦，也许是暂停--但我不建议依赖这些。|4222125|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|S|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|T|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|U|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|V|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|P|$]]

Your first question is how to know when to stop reading, if you don't terminate packets/commands/whatever with a '\n'.

The answer is that you have to build some way of knowing how much to read into the protocol. There's nothing inherent in serial comms that tells you when a sequence ends. It's just a stream of bytes.

<ul>
<li>A delimiter like \n is a common way to do it (stop if you see that you've read a delimiter)</li>
<li>Fixed-length packets (read that many bytes then stop)</li>
<li>Packets containing a "length" field (read the length field, then use that do decide how many more bytes to read)</li>
</ul>

If your protocol does none of these things, there's no way your reader can know when to stop. Oh, maybe with timeouts -- but I wouldn't recommend relying on those.

blocks|key|3340495|text|来自Arduino参考页面(+http://arduino.cc/en/Serial/Print+)：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3340496|Serial.print(78,+HEX)+gives+"4E"+|code-block|syntax|javascript|3340497|所以：|3340498|Serial.print(printbyte,+HEX);|3340499|应该给你你想要的输出。|3340500|entityMap|0|LINK|mutability|MUTABLE|url|http://arduino.cc/en/Serial/Print^0|F|X|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|12|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|C|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

From the Arduino reference pages ( <a href="http://arduino.cc/en/Serial/Print" rel="nofollow">http://arduino.cc/en/Serial/Print</a> ):

<pre><code>Serial.print(78, HEX) gives "4E" 
</code></pre>

So:

<pre><code>Serial.print(printbyte, HEX);
</code></pre>

Should give you the output you desire.

I want to echo back the data sent by Linux to Arduino which is a hex command, because I'll be needing the echoed data for PHP to read. The problem is I don't want to use a newline to print the complete the data. I want to print it when there is no more data to read by the Arduino. Here's the code:

What I'm trying to accomplish:

<ol>
<li>how to spot the end of a sequence of reads if not with a <code>\n</code></li>
<li>how to print hex in your desired format.</li>
</ol>

Arduino code:

<pre><code>char printByte[100];
byte getByte;
int pos = 0;
void setup(){
 Serial.begin(9600);
}

void loop(){
 if(Serial.available() &gt; 0){
 getByte = Serial.read();
 printByte[pos] = getByte;
 pos++;
 printByte[pos] = '\0';

 if(getByte == '\n'){
 Serial.print(printByte);
 for(int i=0; i&lt;=sizeof(printByte);i++){
 printByte[i]=0;
 }
 pos = 0;
 }
 }
}
</code></pre>

Linux sample code in sending hex..

<pre><code>unsigned char pCom[2][7]={{0xFF,0x01,0x00,0x10,0x2F,0x2F,0x6F},
 {0xFF,0x01,0x00,0x08,0x2F,0x2F,0x67}};

write(fd,pCom[0],8);
</code></pre>

Also, how can I trim down in Arduino code, say the <code>0x</code> so it will only ouput <code>FF 01 10</code>, etc.?

Echo the data that is sent by Linux to Arduino

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我想回显Linux发送给Arduino的数据，这是一个十六进制命令，因为我需要PHP读取的回显数据。问题是我不想使用换行符来打印完整的数据。当Arduino没有更多的数据可读取时，我想打印它。下面是代码：我想要做的是：如果没有使用\n，如何识别读取序列的结尾如何以所需格式打印十六进制。Arduino代码：char pr...

问回显Linux发送给Arduino的数据。
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问回显Linux发送给Arduino的数据。EN