If you aren't using Windows NT, 2000 or XP the address of the PIO can either be entered as a hexadecimal value for ISA based cards, or selected from the registry in the case of the PCI PIO cards. If you are using NT, 2k or XP you can install the InstaCal drivers that come with a Computer Boards interface cards or the wretched DriverLINX stuff that comes with the Keithley cards (there's also some auxiliary stuff that's useful for PCMCIA Keithley cards), then the InstaCal card number or the DriverLINX device number can be used allowing windows versions based on NT (NT itself, windows 2000 and XP so far) to use a PIO.
    When listing PCI cards TimeDX can't tell exactly what in the registry is an 8255 (the mere fact that it reads the registry to determine the base address of the 8255 is an extreme hack, utterly undocumented by anyone), it simply hunts for resources that describe groups of 4 I/O ports and lists them as possible candidates along with the device's description.
    When using NT based operating systems only Computer Boards InstaCal cards or Keithley DriverLINX boards will be listed because using direct port I/O under NT will result in immediate protection faults. Additionally the Keithley DriverLINX stuff will have to configure the various ports on the PIO for input and output as you desire because DriverLINX doesn't let applications configure the card. Another failing of the Keitley DriverLINX stuff (it can't handle multiple threads and DMDX is massively multithreaded) would appear to mandate the use of the queued PIO devices in DMDX, the plain PIO12 device will cause DMDX to fail with the second item file run so <id QPIO12> must be used instead.
   
PIO12.

    This is to verify that a MetraByte PIO-12 or ComputerBoards PIO24 has been installed correctly and is indeed functioning. The default address that Dmastr has used in the past for an ISA PIO-12 is port 310 Hex as opposed to 300H that the card ships set to. The correct switch settings for this ISA interface card at 310H read from switch 1 to 8 are OFF, OFF, ON, ON, ON, OFF, ON, ON. Clicking Start causes TimeDX to read the contents of the address edit box and setup an 8255 (the chip that is the PIO) at that address -- if you specify an incorrect address at best you will be unable to see the card, at worst you will have sent commands to some system device and the results can be catastrophic. Clicking Save writes the port address to the registry for DMDX to use.

    Assuming you have some test hardware and can monitor the output of PORT C clicking on the output controls changes the state of that output bit, checked being LOW (which would light a led with the test jig provided below).

    The Inputs are monitored every 20 ms (in this test, for DMDX it is every millisecond), for Dmastr's usage LOW (switched to ground as opposed to pulled up to +5V) is the closed switch state.

    Unused inputs should be pulled up unless they are specifically disabled with the DMDX MIP word. The default value for MIP is 7 enabling pa0, pa1 and pa2, if you aren't using all of those three then the unused ones should ether be pulled up or another MIP value explicitly set in the item file.
   
PIO12 connector.

Pinouts: