Read ASCII 8-bit data from a device plugged in USB port in C#

Question

I have a Electronic balance device which is plugged in to a USB port. The output is continuous at all times, and I can read it by LibUsbDotNet in C#. Transmission codes are ASCII 8-bit codes. And other device information is:

start bit:1bit, Data bit:8bits, Parity bit:0/1 bits, Stop bit:2bits

Data bits (D1-D7) or (D1-D8) are a numerical value (0-9); codes are 30H-39H.

My questions are:

1. How can I read the last data from the device?

2. How do I convert them (bytes) to ASCII 8-bit (30H-39H) so that understand their numbers?

My code is:

private void cmdRead_Click(object sender, EventArgs e)
{
    cmdRead.Enabled = false;
    byte[] readBuffer = new byte[64];
    int uiTransmitted;
    ErrorCode eReturn;
    if ((eReturn = mEpReader.Read(readBuffer, 1000, out uiTransmitted)) == ErrorCode.None)
    {
        tsStatus.Text = uiTransmitted + " bytes read.";
        showBytes(readBuffer, uiTransmitted);
    }
    else
        tsStatus.Text = "No data to read! " + eReturn;

    cmdRead.Enabled = true;
}
private void showBytes(byte[] readBuffer, int uiTransmitted)
{
    if (ckShowAsHex.Checked)
    {
        // Convert the data to a hex string before displaying
        string hex = GetHexString(readBuffer, 0, uiTransmitted).ToString();
        tRecv.AppendText(hex);
        tRecv.AppendText(Environment.NewLine);
    }
    else
    {
        // Display the raw data
        tRecv.AppendText(Encoding.UTF8.GetString(readBuffer, 0, uiTransmitted));
        tRecv.AppendText(Environment.NewLine);
    }
}
private static StringBuilder GetHexString(byte[] data, int offset, int length)
{
    StringBuilder sb = new StringBuilder(length * 3);
    for (int i = offset; i < (offset + length); i++)
    {
        sb.Append(data[i].ToString("X2") + " ");
    }
    return sb;
}

I can upload the project if required. For example, when the device shows 3.04, the value that the application returns is:

01 62 21 60 68 38 7F 60 78 61 60 28 6D 7F 61 40 7F 69 61 62 79 69 79 79 78 79 79 20 78 69 61 21 20 68 20 61 68 7F 6B 63 61 7B 60 78 39 6D 7F 60 41 28 69 7F 60 63 01 4F 7F 60 78 69 79 69 40 69 

How can I find the value that devices show from the above response or how can I get correct data (correct encode) from the device?

Answer 1

As mentioned at this comment by Hans Passant, The COM-To-USB port adapter had installed a new COM port and that works exactly as what manufacture was mentioned in its document. All received lines from that COM port was ready to use ASCII codes.