I create a new project called TEST.

Went to Project - New Source File
- Names the file TestUnitOne
Modified the file as follows:

Code:
unit TestUnitOne;

interface
	{ add public declarations here }
	Procedure WriteHeading;

implementation
	{ add unit functions & procedures here }
	Procedure WriteHeading;
	  Begin
	    DrawText('HEADING',10,10);
	  end;

initialization
	{ add initialization code here }
end.
Went back tot he main file and modified it as follows (Uses clause and drawtext line):

Code:
program Test;

Uses
  TestUnitOne;
  
begin
	WriteHeading;
	repaint;	
	delay(2000);
end.
Seems to work fine.