parallel breakout board

Discussion in 'The Projects Forum' started by lancellot07, Jan 17, 2013.

  1. lancellot07

    Thread Starter New Member

    Jul 2, 2012
    17
    0
    i found this schematic somewhere in the internet and would like to ask if this is functional.. picture is attached..

    and if anybody could direct me to other sites that has a very simple schematics on parallel port breakout board..

    thanks
     
    Last edited: Jan 17, 2013
  2. nerdegutta

    Moderator

    Dec 15, 2009
    2,515
    785
    Interesting.

    Which software are you going to use?
     
  3. lancellot07

    Thread Starter New Member

    Jul 2, 2012
    17
    0
    emc or probably mach2
     
  4. KrisBlueNZ

    Member

    Oct 17, 2012
    111
    14
    Back 10 years ago, or more, a PC parallel port could be used for general purpose parallel interfacing to external hardware such as stepper motors. You still had to provide an external +5V power supply, because the port cannot supply much current (a few mA). Nowadays, the 25-pin parallel connector is unheard-of because printers are all USB-interfaced. In between then and now, many 25-pin parallel ports used hardware that would not provide steady output signals, presumably to save power. I believe (but have not confirmed) that these ports only asserted the eight data signals when an actual data strobe was in progress; at other times, they would tri-state the data outputs.

    Many parallel ports also supported multiple modes - SPP (standard), PS/2, EPP and ECP. Obviously to use one of these as a standard port, you need to set it to SPP compatibility. This is normally done through the BIOS Setup.

    Also, multi-tasking operating systems (Windows, at least) do not normally allow user software to access the parallel port registers directly; you can access them directly under MS-DOS, Windows 3.x and Windows 95/98, but anything newer requires a DLL to allow an application program to access the hardware directly. Google "direct i/o dll".

    So that circuit used to be appropriate; whether it will work for you depends on what operating system and hardware you have.
     
  5. lancellot07

    Thread Starter New Member

    Jul 2, 2012
    17
    0
    so this wil work for older version of wndows..thats alright.. im gonna use win98. i have an old pc and win98 installer.. thanks very much..
     
  6. atschirner

    New Member

    Jan 23, 2013
    2
    0
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