The following code write file to SD card on Netduino Plus 4.2 OK. But fails on ND3 4.3.
The code reads the file back under debug OK. But the file is empty on the SD card when opened in NotePad app .Please help.
public static void Main()
{ // reads from analog input port A0 and write to the file test.txt
const double maxVoltage = 3.3;
lightSensor.Scale = maxVoltage;
lightSensor.Offset = 0.0;
double voltagevalue = 0;
using (var filestream = new FileStream(@"SD\test.txt", FileMode.OpenOrCreate))
{
StreamWriter streamWriter = new StreamWriter(filestream);
for (int i = 0; i < 10; i++)
{ // use a 10k pot to trim the resistor value
voltagevalue = lightSensor.Read();
streamWriter.WriteLine("Light Level=" + voltagevalue.ToString() + DateTime.Now.ToString().ToString());
Debug.Print(voltagevalue.ToString("f3"));
Thread.Sleep(1000);
}
streamWriter.Flush();
streamWriter.Close();
}
using (var filestream = new FileStream(@"SD\test.txt", FileMode.Open))
{
StreamReader reader = new StreamReader(filestream); // reader object
Debug.Print(reader.ReadToEnd());
reader.Close();
}
}