生成一段vb代码，要求com口接收数据，画出数据曲线。

以下是基于VB的串口数据接收和曲线绘制代码：

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        '打开串口
        SerialPort1.PortName = "COM1"
        SerialPort1.BaudRate = 9600
        SerialPort1.DataBits = 8
        SerialPort1.StopBits = IO.Ports.StopBits.One
        SerialPort1.Parity = IO.Ports.Parity.None
        SerialPort1.ReadTimeout = 1000
        SerialPort1.WriteTimeout = 1000
        SerialPort1.Open()

        '初始化曲线
        Chart1.Series.Clear()
        Chart1.Series.Add("Data")
        Chart1.Series("Data").ChartType = DataVisualization.Charting.SeriesChartType.Line
        Chart1.Series("Data").BorderWidth = 2
        Chart1.Series("Data").Color = Color.Red
        Chart1.ChartAreas(0).AxisX.Minimum = 0
        Chart1.ChartAreas(0).AxisY.Minimum = 0
    End Sub

    Private Sub SerialPort1_DataReceived(sender As Object, e As IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
        '读取串口数据
        Dim data As String = SerialPort1.ReadLine()
        Dim value As Integer

        '转换数据格式
        Try
            value = Convert.ToInt32(data)
        Catch ex As Exception
            Exit Sub
        End Try

        '更新曲线
        Me.Invoke(Sub() Chart1.Series("Data").Points.AddY(value))
    End Sub

    Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing
        '关闭串口
        SerialPort1.Close()
    End Sub
End Class

该代码实现了对COM1串口的数据接收，并将接收到的数据以曲线的形式绘制在Windows Form应用程序的窗体中。需要注意的是，该代码只是一个示例，实际应用时需要根据具体的串口设备和数据格式进行相应的修改。