Simple PhotoCell Timing System
(S.P.T.S.)
INSTALLATION SUMMARY

(c) Bryan Brown & Art McEwen 1997-1999
All rights reserved, not to be copied without permission.



  1. Load CHITI.EXE and test the LPT port by turning a printer (connected to the port) on and off. You should see an immediate change in the main CHITI display screen, telling you which port you are connected to (LPT1/2/3). It should also change the status of several data bits each time you power on or off.

  2. Uniquely identify and test all of your PhotoCells with a Multimeter. Measure and record the "Bright" and "Dark" Resistances for each PCell per the instructions in the "All About PhotoCells" section.

  3. Measure and record the "Trigger Points" of the port/pins that you will be using following the instructions in the "Trigger Points" section. Note - This is an optional step, however, if you have problems getting your computer to recognize the PCells, you are going to have to do this step. It's a good idea to do this up front as it will increase your understanding of PCells and their operation.

  4. Build a small simulated track platform from a scrap of wood so you can do your testing in the comfort of an upright position. Working underneath a table, while lying on your back and working over your head is no way to learn about PhotoCells, believe me!!!

  5. Wire up the selected PhotoCells and DB25 connector but don’t connect to computer yet.

  6. Test resistances through the DB25 connector, experiment with distance and intensity of light sources and watch the effect on your Multimeter.

  7. Ensure that there is suitable resistance in each circuit in your DB25/Pcell wiring harness with light source at its brightest position. Generally, there should always be at least 500 ohms of resistance in the circuit. It is only when you get an extreme port that you should have a resistance less than 500 ohms (like my Pin 10 on "Lucifer"). Don't have a circuit with no resistance or you risk damaging your computer.

  8. Plug in DB25 connector to computer.

  9. Run CHITI using small simulated track platform and pass hand over sensor to simulate car. The data bit should be "BRIGHT" during the normal Fully Lit condition and it should turn "DARK" when a car passes over the sensor or stops on the sensor.

  10. Proceed to the track. Drill holes in track surface, install small block under table or bent coat hanger, insert and secure PhotoCell with pin/nail or tape.

  11. Repeat testing with CHITI and test using actual slot cars.

  12. Edit the PARM.TXT file, put in the correct port identifier, your track name and set the Minimum Lap Time for your track.

  13. Load and run one of DINO/ENZO/MONTY/PROST and continue testing using actual slot cars.

  14. Fine tune source lighting and PhotoCell positioning.

  15. Have your first timed race and see who can set fastest lap.

  16. Email Art or Bryan and tell them how much fun you had doing this all by yourself.

  17. Send small donation to Scuderia McEwen R&D.

  18. Receive all the "Advanced Software" like LEMANS, BERNIE, MARIO, AYRTON, NICKI etc and do some serious slotting.

  19. Tell your friends how great S.P.T.S. is and how easy it is to install!



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