[
  uuid(06CCA034-4AD3-456C-8A63-F5B27DD26767),
  version(1.0),
  helpstring("Pulsograph COM library (c)2013 cpp.in.ua")

]
library Pulse
{

  importlib("stdole2.tlb");

  interface ICoDevice;
  coclass CoDevice;
  interface ICoRecord;
  coclass CoRecord;

  [
    uuid(50D29AE0-1F0D-48D5-8147-774101A51554),
    version(1.0),
    helpstring("Interface for access the device"),
    dual,
    oleautomation
  ]
  interface ICoDevice: IDispatch
  {
    [id(0x000000C9), helpstring("Checks whether the device is online")]
    HRESULT _stdcall IsConnected([out, retval] long* RetIsCon);
    [id(0x000000CA), helpstring("Request connection to the device")]
    HRESULT _stdcall Connect([out, retval] long* RetIsCon);
    [id(0x000000CB), helpstring("Disconnecting the device")]
    HRESULT _stdcall Disconnect(void);
    [id(0x000000CC), helpstring("Read ADC data")]
    HRESULT _stdcall GetRawData([out, retval] SAFEARRAY(long) * RetData);
    [id(0x000000CD), helpstring("Get current heart rate")]
    HRESULT _stdcall GetHeartRate([out, retval] float* RetHR);
    [id(0x000000CE), helpstring("Get current carrier frequency signal level")]
    HRESULT _stdcall GetDcOffset([out, retval] long* RetOffs);
    [id(0x000000CF), helpstring("Get current control value of AC carrier amplifier")]
    HRESULT _stdcall GetHfAmp([out, retval] long* RetAmp);
    [id(0x000000D0), helpstring("Get current control value of LF pulse wave amplifier")]
    HRESULT _stdcall GetLfAmp([out, retval] long* RetAmp);
  };

  [
    uuid(94AC0D9B-039A-467E-91AB-2F6CD6C9B7A1),
    version(1.0),
    helpstring("Dispatch interface for accessing pletismograph record"),
    dual,
    oleautomation
  ]
  interface ICoRecord: IDispatch
  {
    [id(0x000000C9), helpstring("Open existing record")]
    HRESULT _stdcall OpenFile([in] BSTR InFileName, [out, retval] long* RetIsOk);
    [id(0x000000CA), helpstring("Get length of the record (in seconds)")]
    HRESULT _stdcall GetLength([out, retval] float* RetLength);
    [id(0x000000CB), helpstring("Change current read position in record")]
    HRESULT _stdcall GoToPos([in] float InPos, [out, retval] float* RetPos);
    [id(0x000000CC), helpstring("Check current read position")]
    HRESULT _stdcall GetPos([out, retval] float* RetPos);
    [id(0x000000CD), helpstring("Get data samples from the record")]
    HRESULT _stdcall ReadSamples([in] long InCount, [out, retval] SAFEARRAY(long) * RetData);
    [id(0x000000CE), helpstring("Read heart rate near the current position")]
    HRESULT _stdcall GetHeartRate([out, retval] float* RetHR);
  };

  [
    uuid(2A04AC47-567C-4EF7-A826-E12E00C01E07),
    version(1.0),
    helpstring("CoDevice Object")
  ]
  coclass CoDevice
  {
    [default] interface ICoDevice;
  };

  [
    uuid(4BC48BAE-A164-4C7B-B25C-034AD7E4556C),
    version(1.0),
    helpstring("CoRecord Object")
  ]
  coclass CoRecord
  {
    [default] interface ICoRecord;
  };

};

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using System.Runtime.InteropServices;

namespace C_Sharp_Test
{
    public partial class TestForm : Form
    {
        Pulse.ICoDevice pdev;
        Pulse.ICoRecord prec;
        int ipos;
        public TestForm()
        {
            InitializeComponent();
            pdev = null;
            prec = null;
        }

        private void ComCreateButton_Click(object sender, EventArgs e)
        {
            if (pdev == null)
            {
                pdev = new Pulse.CoDevice();
                if (pdev != null)
                    PaintTimer.Enabled = pdev.IsConnected() != 0;
            }
            if (prec == null)
            {
                prec = new Pulse.CoRecord();
            }

            if (pdev != null)
            {
                TextB.Text = "CoDevice OK\r\n";
            }
            else
            {
                TextB.Text = "CoDevice FAILED\r\n";
            }

            if (prec != null)
            {
                TextB.Text += "CoRecord OK";
            }
            else
            {
                TextB.Text += "CoRecord FAILED";
            }
        }

        private void ComDestroyButton_Click(object sender, EventArgs e)
        {
            if (pdev != null)
            {
                Marshal.ReleaseComObject(pdev);
                pdev = null;
            }
            if (prec != null)
            {
                Marshal.ReleaseComObject(prec);
                prec = null;
            }
        }

        private void ConnectButton_Click(object sender, EventArgs e)
        {
            if (pdev == null) return;
            if(pdev.IsConnected() == 0)
                pdev.Connect();
            else
                pdev.Disconnect();

            PaintTimer.Enabled = pdev.IsConnected() != 0;
        }

        private void PaintTimer_Tick(object sender, EventArgs e)
        {
            if (pdev == null) return;

            // process ADC data
            Array sa = pdev.GetRawData();
            int len = sa.GetLength(0);

            System.Windows.Forms.DataVisualization.Charting.Series ps = TestChart.Series.FindByName("TestSeries");
            for(int i = 0; i < len; i++){
                ps.Points.AddXY(ipos * 0.01, sa.GetValue(i));
                ipos++;
            }

            if (ipos > 1000){
                ps.Points.Clear();
                ipos = 0;
            }
            // display numerical values            
            TextB.Text = "HR " + pdev.GetHeartRate() +
                " \r\nDC offset " + pdev.GetDcOffset() +
                " \r\nHF amp " + pdev.GetHfAmp() +
                " \r\nLF amp " + pdev.GetLfAmp();

        }

        private void RecOpenButton_Click(object sender, EventArgs e)
        {
            if (prec == null) 
                return;
            pdev.Disconnect();
            PaintTimer.Enabled = false;

            if (RecOpenDialog.ShowDialog() == DialogResult.OK)
            {
                int res = prec.OpenFile(RecOpenDialog.FileName);
                if (res == 0)
                {
                    TextB.Text = "Can't open " + RecOpenDialog.FileName;
                    return;
                }
                TextB.Text = "OpenFile OK " + RecOpenDialog.FileName;
                RecPosTB.Maximum = (int)prec.GetLength() + 1;
                RecPosTB.Value = 0;
                RecPosTB_ValueChanged(sender, e);
            }
        }

        private void RecPosTB_ValueChanged(object sender, EventArgs e)
        {
            if (prec == null) return;
            prec.GoToPos(RecPosTB.Value);

            Array sa = prec.ReadSamples(500);
            int len = sa.GetLength(0);

            System.Windows.Forms.DataVisualization.Charting.Series ps = TestChart.Series.FindByName("TestSeries");
            ipos = 0;
            ps.Points.Clear();
            for (int i = 0; i < len; i++)
            {
                ps.Points.AddXY(ipos * 0.01, sa.GetValue(i));
                ipos++;
            }

            // display numerical values            
            TextB.Text = "HR " + prec.GetHeartRate() +
                " \r\nPos (s) " + prec.GetPos();
        }

    }
}

unit MainUnit;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComObj, ActiveX, ExtCtrls, ComCtrls;

type
  TMainForm = class(TForm)
    CreateComButton: TButton;
    DestroyComButton: TButton;
    ConnectButton: TButton;
    PaintTimer: TTimer;
    PBPanel: TPanel;
    PB: TPaintBox;
    LogMemo: TMemo;
    RecPosTB: TTrackBar;
    RecOD: TOpenDialog;
    RecOpenButton: TButton;
    procedure CreateComButtonClick(Sender: TObject);
    procedure DestroyComButtonClick(Sender: TObject);
    procedure ConnectButtonClick(Sender: TObject);
    procedure PaintTimerTimer(Sender: TObject);
    procedure RecOpenButtonClick(Sender: TObject);
    procedure RecPosTBChange(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;
  pdev, prec: Variant;
  ind: Integer;

implementation

{$R *.dfm}

procedure TMainForm.CreateComButtonClick(Sender: TObject);
begin
  if not VarIsClear(pdev) then exit;

  try
    pdev := CreateOleObject('Pulse.CoDevice');
    prec := CreateOleObject('Pulse.CoRecord');
  except
    // something wrong
    LogMemo.Text := 'Can`t create COM objects!';
    exit;
  end;
    LogMemo.Text := 'Create COM objects is OK';

  if not VarIsClear(pdev) then PaintTimer.Enabled := pdev.IsConnected <> 0;

end;

procedure TMainForm.DestroyComButtonClick(Sender: TObject);
begin
  if not VarIsClear(pdev) then
  begin
      pdev := Unassigned;
  end;
  if not VarIsClear(prec) then
  begin
      prec := Unassigned;
  end;
end;

procedure TMainForm.ConnectButtonClick(Sender: TObject);
begin
  if VarIsClear(pdev) then exit;

  if pdev.IsConnected then pdev.Disconnect
  else pdev.Connect;

  if pdev.IsConnected then PaintTimer.Enabled := true;

end;

procedure TMainForm.PaintTimerTimer(Sender: TObject);
var
  psa : PSafeArray;
  cnt, i, y, pbx, pby : Integer;
  mx, my : Real;
begin
  if VarIsClear(pdev) then exit;
  psa := PSafeArray(TVarData(
                              pdev.GetRawData
                              ).VArray);
  SafeArrayGetUBound(psa, 1, cnt);

  // paint the data
  if ind = 0 then
  begin
    PB.Canvas.FillRect(PB.Canvas.ClipRect);
  end;

  mx := PB.Width / 500;
  my := PB.Height / 1024;
  for i := 0 to cnt do
  begin
    SafeArrayGetElement(psa, i, y);
    pbx := Round(ind * mx);
    pby := PB.Height - Round(my * y);
    if ind = 0 then PB.Canvas.MoveTo(pbx, pby);
    PB.Canvas.LineTo(pbx, pby);
    ind := ind + 1;
  end;
  if ind * mx > PB.Width then ind := 0;

  LogMemo.Clear;
  LogMemo.Lines.Add('HR ' + FloatToStr(pdev.GetHeartRate));
  LogMemo.Lines.Add('DC offset ' + IntToStr(pdev.GetDcOffset));
  LogMemo.Lines.Add('HF amp ' + IntToStr(pdev.GetHfAmp));
  LogMemo.Lines.Add('LF amp ' + IntToStr(pdev.GetLfAmp));

end;

procedure TMainForm.RecOpenButtonClick(Sender: TObject);
var
  len : real;
begin
  if not VarIsClear(pdev) then
  begin
    pdev.Disconnect;
    PaintTimer.Enabled := false;
  end;

  if VarIsClear(prec) or not RecOD.Execute then exit;

  if prec.OpenFile(RecOD.FileName) = 0 then
  begin
    LogMemo.Text := 'Can`t open ' + RecOD.FileName;
    exit;
  end
  else
    LogMemo.Text := 'Open OK ' + RecOD.FileName;

  len := prec.GetLength;
  RecPosTB.Max := Round(len);
  RecPosTB.Position := 0;
  RecPosTBChange(Sender);

end;

procedure TMainForm.RecPosTBChange(Sender: TObject);
var
  psa : PSafeArray;
  cnt, i, y, pbx, pby : Integer;
  mx, my : Real;
begin
  if VarIsClear(prec) then exit;

  prec.GoToPos(RecPosTB.Position);

  psa := PSafeArray(TVarData(
                              prec.ReadSamples(500)
                              ).VArray);
  SafeArrayGetUBound(psa, 1, cnt);

  // paint the data
  ind := 0;
  PB.Canvas.FillRect(PB.Canvas.ClipRect);

  mx := PB.Width / 500;
  my := PB.Height / 2000;
  for i := 0 to cnt do
  begin
    SafeArrayGetElement(psa, i, y);
    pbx := Round(ind * mx);
    pby := PB.Height - Round(my * (y + 1000));
    if ind = 0 then PB.Canvas.MoveTo(pbx, pby);
    PB.Canvas.LineTo(pbx, pby);
    ind := ind + 1;
  end;

  LogMemo.Clear;
  LogMemo.Lines.Add('HR ' + FloatToStr(prec.GetHeartRate));
  LogMemo.Lines.Add('Pos (s) ' + IntToStr(prec.GetPos));

end;

end.