diff --git a/mdl/m_io_base.pas b/mdl/m_io_base.pas
new file mode 100644
index 0000000..9dcce65
--- /dev/null
+++ b/mdl/m_io_base.pas
@@ -0,0 +1,118 @@
+Unit m_io_Base;
+
+{$I M_OPS.PAS}
+
+Interface
+
+Const
+  TIOBufferSize = 8 * 1024 - 1;
+
+Type
+  TIOBuffer = Array[0..TIOBufferSize] of Char;
+
+  TIOBase = Class
+    FInBuf     : TIOBuffer;
+    FInBufPos  : LongInt;
+    FInBufEnd  : LongInt;
+    FOutBuf    : TIOBuffer;
+    FOutBufPos : LongInt;
+
+    Constructor Create; Virtual;
+    Destructor  Destroy; Override;
+    Procedure   PurgeInputData;
+    Procedure   PurgeOutputData;
+    Function    DataWaiting     : Boolean; Virtual;
+    Function    WriteBuf        (Var Buf; Len: LongInt) : LongInt; Virtual;
+    Function    ReadBuf         (Var Buf; Len: LongInt) : LongInt; Virtual;
+    Procedure   BufWriteChar    (Ch: Char); Virtual;
+    Procedure   BufWriteStr     (Str: String); Virtual;
+    Procedure   BufFlush; Virtual;
+    Function    WriteStr (Str: String) : LongInt; Virtual;
+    Function    WriteLine       (Str: String) : LongInt; Virtual;
+    Function    ReadLine        (Var Str: String) : LongInt; Virtual;
+    Function    WaitForData     (TimeOut: LongInt) : LongInt; Virtual;
+    Function    PeekChar        (Num: Byte) : Char; Virtual;
+    Function    ReadChar        : Char; Virtual;
+  End;
+
+Implementation
+
+Constructor TIOBase.Create;
+Begin
+  Inherited Create;
+
+  FInBufPos  := 0;
+  FInBufEnd  := 0;
+  FOutBufPos := 0;
+End;
+
+Destructor TIOBase.Destroy;
+Begin
+  Inherited Destroy;
+End;
+
+Procedure TIOBase.PurgeOutputData;
+Begin
+  FOutBufPos := 0;
+End;
+
+Procedure TIOBase.PurgeInputData;
+Var
+  Buf : Array[1..2048] of Char;
+Begin
+  FInBufPos := 0;
+  FInBufEnd := 0;
+
+  While DataWaiting Do
+    ReadBuf(Buf, SizeOf(Buf));
+End;
+
+Function TIOBase.DataWaiting : Boolean;
+Begin
+End;
+
+Function TIOBase.WriteBuf (Var Buf; Len: LongInt) : LongInt;
+Begin
+End;
+
+Procedure TIOBase.BufFlush;
+Begin
+End;
+
+Procedure TIOBase.BufWriteChar (Ch: Char);
+Begin
+End;
+
+Procedure TIOBase.BufWriteStr (Str: String);
+Begin
+End;
+
+Function TIOBase.ReadChar : Char;
+Begin
+End;
+
+Function TIOBase.PeekChar (Num: Byte) : Char;
+Begin
+End;
+
+Function TIOBase.ReadBuf (Var Buf; Len: LongInt) : LongInt;
+Begin
+End;
+
+Function TIOBase.ReadLine (Var Str: String) : LongInt;
+Begin
+End;
+
+Function TIOBase.WriteStr (Str: String) : LongInt;
+Begin
+End;
+
+Function TIOBase.WriteLine (Str: String) : LongInt;
+Begin
+End;
+
+Function TIOBase.WaitForData (TimeOut: LongInt) : LongInt;
+Begin
+End;
+
+End.