TCP input data packets are combined in Dart - dart

Question

I have a simple TCP client in dart:
import 'dart:io';
void main() {
const sendData = "\$I,Z,0.5,5,0*\r\n";
final socket = Socket.connect("192.168.1.100", int.parse("8008"))
.timeout(Duration(seconds: 5))
.whenComplete(() {
print("Connected!");
}).catchError((_) {
print("Error!");
});
socket.then((soc) {
soc.write(sendData);
soc.listen((data) {
print(String.fromCharCodes(data).trim);
});
});
}
This program sends a special message to server and after that, the server sends back a bunch of data every 10 ms. The output is as follows:
$I,1,250,0,206*$I,1,248,0,192*$I,1,246,0,178*$I,1,245,0,165*
$I,1,244,0,153*$I,1,244,0,141*$I,1,244,0,131*$I,1,245,0,121*
$I,1,246,0,113*$I,1,248,0,105*$I,1,250,0,98*
$I,1,253,0,92*$I,2,0,0,86*$I,2,4,0,82*$I,2,8,0,79*$I,2,12,0,76*
$I,2,18,0,74*$I,2,23,0,74*$I,2,29,0,74*$I,2,36,0,75*$I,2,42,0,77*$I,2,50,0,80*$I,2,58,0,84*$I,2,66,0,89*$I,2,74,0,94*
$I,2,83,0,101*$I,2,93,0,109*$I,2,103,0,117*$I,2,113,0,126*$I,2,124,0,136*$I,2,134,0,147*
$I,2,146,0,159*$I,2,157,0,171*$I,2,169,0,185*$I,2,182,0,199*$I,2,194,0,214*$I,2,207,0,230*$I,2,220,0,246*$I,2,233,1,8*$I,2,247,1,26*$I,3,5,1,44*$I,3,19,1,64*$I,3,33,1,84*
$I,3,48,1,105*$I,3,63,1,126*$I,3,77,1,148*$I,3,93,1,171*$I,3,108,1,194*$I,3,123,1,217*
$I,3,138,1,242*$I,3,154,2,10*$I,3,169,2,35*$I,3,185,2,61*$I,3,201,2,87*$I,3,216,2,113*$I,3,232,2,140*$I,3,248,2,167*$I,4,7,2,195*
$I,4,23,2,223*$I,4,39,2,251*$I,4,54,3,23*$I,4,70,3,51*
The server sends data in $I,1,250,0,206* format, i.e. starts with $ and ends with *. As one may note, several consecutive data packages are concatenated incorrectly.
Whenever I increase the interval, for example to 200 ms, everything is ok.
What should I do?
UPDATE
Besides the BrettSutton answer which is true, the contributers in dart github gave a more complete answer here.
I decided to parse the packet in Socket listen handler, split that and append it to a list. As I want to show the data on a chart, I reset the list after 100 data. However the data could be logged as well.
soc.listen((data) {
var av = data.length;
if (av != 0) {
var stList = String.fromCharCodes(data).trim().split("\$");
stList.forEach((str) {
if (str.isNotEmpty) {
var strS = str.split(",");
if (strS != null) y = parseData(strS);
sampleList.add(y);
}
});
print(sampleList);
if (sampleList.length > 100) {
sampleList.clear();
}
print("==========");
}
});