Read Weight from a Serial Mettler Toledo Digital Scale

问题

I am trying to read weight from digital scale in c# app, found this question this is exactly what I am trying to do but for me below function never runs.

private void port_DataReceived(object sender, SerialDataReceivedEventArgs e) 
{ 
this.Invoke(new EventHandler(DoUpdate)); 
} 

I have checked the scale in device manager, its location is set to Port_#0004.Hub_#0003 and appear to be working fine I was not sure about port number of the scale so I did

var test = SerialPort.GetPortNames();

and only COM1 gets returned

Edit 1: When I do int a = port.ReadByte(); my application hangs and execution never moves forward from this statement.

回答1:

I faced a problem like this and I solved it changing a COM configuration (Configuration > Comunication > Conections) to SICS in the device. I don't know your scale model but maybe my code can help. [Reading data from Mettler Toledo (IND560) scale device using C#]

回答2:

Could you try polling instead of using the DataReceived event? Also, I believe the DataReceived event has a threshold before it fires, you might want to look into that too.

回答3:

Are you able to get the serial number from the balance? This should be the first thing you do when connecting. It will let you verify the connection is established. If you are having trouble connecting through a C# interface try using HyperTerminal first. You can vary a lot of setting really quickly and dial in on the right ones to use. Although the balance should be able to use a wide variety of baud rates and stop bits and such. They are usually pretty adaptable. But do try HyperTerminal.

I'm looking for the pdf but there is a very long list of available commands (depending on your model). The pdf is like 130 pages long. Have you read this?

回答4:

Please see this post, I used Mike library to connect.

using System;
using System.Linq;
using System.Text;
using HidLibrary;

namespace MagtekCardReader
{
    class Program
    {
        private const int VendorId = 0x0801;
        private const int ProductId = 0x0002;

        private static HidDevice _device;

        static void Main()
        {
            _device = HidDevices.Enumerate(VendorId, ProductId).FirstOrDefault();

            if (_device != null)
            {
                _device.OpenDevice();

                _device.Inserted += DeviceAttachedHandler;
                _device.Removed += DeviceRemovedHandler;

                _device.MonitorDeviceEvents = true;

                _device.ReadReport(OnReport);

                Console.WriteLine("Reader found, press any key to exit.");
                Console.ReadKey();

                _device.CloseDevice();
            }
            else
            {
                Console.WriteLine("Could not find reader.");
                Console.ReadKey();
            }
        }

        private static void OnReport(HidReport report)
        {
            if (!_device.IsConnected) { return; }

            var cardData = new Data(report.Data);

            Console.WriteLine(!cardData.Error ? Encoding.ASCII.GetString(cardData.CardData) : cardData.ErrorMessage);

            _device.ReadReport(OnReport);
        }

        private static void DeviceAttachedHandler()
        {
            Console.WriteLine("Device attached.");
            _device.ReadReport(OnReport);
        }

        private static void DeviceRemovedHandler()
        {
            Console.WriteLine("Device removed.");
        }
    }
}

来源：https://stackoverflow.com/questions/9671294/read-weight-from-a-serial-mettler-toledo-digital-scale