Splitting the data received from serial port

Question

Hello,

I'm having a problem trying to solve how to split data received from serial port. The basic idea is to receive measurement data from serial port and then save it to .xml file.

So far I have other "modules" in my software working but I haven't yet figured how to split the data and save it to the .xml file properly. The data I receive is a list of measurement values separated by comma and with start and stop letters. length and form of the received data will be always same, only measurement values change...

So it'll look like this: &,24,21,53,54,33,24,36,37,54,33,33,22,33,23,$

How should this be splitted so that it would be easiest to save to .xml file?

form of the .xml file is something like:
<sensor1>
<name>temp1</name>
<value>"first received value"</value>
</sensor1>

I'm quite new to C#, previously I have coded only C-language and some HTML stuff, so my ideas might have been a bit too "conservative" ;)

- Vertti

Samuel Vaesy · Answer

Okay, Thanks for helping, now I've getting to understand this "language" a bit better :) This code example you gave me works so far quite well, but there is one thing which I believe didn't occur in my example of the contents of the original .xml file, and because of that this example of yours doesn't work like my actual idea was originally. There are several temperature sensors in my "project" and they need to have somekind of description. And in my example this node is the description... So the description can be somethin like "outside temp1", "outside temp2" or "inside temp1" or "ambient tempX". This example code obviously generates new .xml file and all the content to it according to these xmlwriter "parameters" with increasing index, so this doesn't work in this case... Is there some neat way to make a copy of the original file and update measurement values to it?

Alan · Answer

It's best to split the values first (assuming the start and end characters are present) and then iterate through the resulting array and add them to the xml file. Something like this: using System.Xml; // .... string data = SP.ReadExisting(); if (data.StartsWith("&,") && data.EndsWith(",$")) { string[] values = data.Substring(2, data.Length - 4).Split(','); XmlWriterSettings settings = new XmlWriterSettings(); settings.Indent = true; using (XmlWriter writer = XmlWriter.Create("measurement.xml", settings)) { writer.WriteStartElement("measurement"); for (int i = 0; i { writer.WriteStartElement("sensor" + (i + 1).ToString()); writer.WriteStartElement("name"); writer.WriteString("temp" + (i + 1).ToString()); writer.WriteEndElement(); // writer.WriteStartElement("value"); writer.WriteString(values[i].ToString()); writer.WriteEndElement(); // writer.WriteEndElement(); // } writer.WriteEndElement(); // writer.Flush(); } } Using the specimen data you posted earlier, the resulting xml file should look like this: temp1 24 temp2 21 temp3 53 temp4 54 temp5 33 temp6 24 temp7 36 temp8 37 temp9 54 temp10 33 temp11 33 temp12 22 temp13 33 temp14 23 As I wasn't sure what to put in the childnodes, I've just put something generic for now.

Samuel Vaesy · Answer

Hmm... so just to clarify a bit what I'm after... A microcontroller measures temperatures from certain process with several different sensors, after measurements are ready, it sends those values to serial port, and it adds starting mark "&" and an end mark "$". Amount of sensors is always the same(if it does matter), and value can be either 1, 2 or 3 numbers long. These measurement values needs to be stored to the .xml file, so that first value after starting mark(&) goes to the childnode of node and second value to of and so on... So, is it neater to first copy these splitted values to to some array and then save to .xml file, or to save one value at a time during the "splitting process"? So, would something like this work? string received = SP.ReadExisting(); string[] values = received.Split(','); Also it would be good to have this to start the splitting only if the first received mark is "&" and if it doesn't receive "$" after n numer of values it "resets"... but this I can probably figure out myself... - Vertti

Alan · Answer

Well, splitting the data received is easy enough: string data = "&,24,21,53,54,33,24,36,37,54,33,33,22,33,23,$"; string[] values = data.Substring(2, data.Length - 4).Split(','); though I'm not entirely clear what goes where in the XML file or can you sort that bit out yourself?

Splitting the data received from serial port

Answers (4)