Direct Access to API

The LogicPD control software GUI is tedious to use for repeated experiments, and cannot be scripted. Defining a pattern sequence requires that you click the "add" button, navigate to a file (the file choose defaults to only displaying BMP images), select and add it, optionally choose a threshold value, and click OK. Then it takes a few seconds to convert the file to the native DBI format. For a sequence of hundreds of patterns, this can take a very long time, and making changes to the patterns will be tedious and error-prone. Fortunately, the DBI format is very simple and can be reverse engineered. Even more fortunately, all the important bits are implemented in a DLL file (the control software simply calls this) and one of those DLL functions can execute a batch file (text file) containing commands that map directly onto DLL functions. It's very easy to call these functions from Python. See the attached script for an example of how to generate the DBI files and display them in sequence. There are some tricky aspects to this (particularly dealing with triggers), described in more detail in the script comments. To run the script, make sure that PortabilityLayer.dll and DlpCommDLL.dll (from the SDK) are in the same directory.

-- BradAtcheson - 20 Sep 2011

• On the Acer Aspire netbook (Windows 7), plugging the HDMI cable in and switching the projector on is a sure-fire way to cause a blue-screen-of-death.

Loading Images

Images can be loaded via the DLP software application. This requires generating (max) 1024x768 images and loading each one via the GUI. The software will convert these to DBI files. The DBI format is not published, nor is there an external tool to produce these images. However, the software will produce a DBI file from the loaded patterns, and save it to the hard drive. It's apparently fairly straightforward to reverse-engineer this format.

1. Switch projector on

• http://focus.ti.com/lit/an/dlpa024a/dlpa024a.pdf , Or local copy

1. Install, then look at the installation directory ( "Program Files\Texas Instruments-DLP\ DLP LightCommander API Ref Apps\" )

The software has different solutions, which have different projects contained within them. The easiest method to creating a new project is using the wizard found in the "New" menu. Note that that bits per pixel is specified when creating a project. Also, switching between Structured Light and Video modes does not always seem to work; creating a new project is often necessary.

Important: Make sure that the DLP Light Commander is plugged in via USB and turned on (in "run" mode) before starting the software.

The USB cable is used to change real-time settings (such as flipping the image horizontally or vertically) and to compile and download a program to the projector. Once the projector has its program in memory, you can unplug the USB cable and the projector will continue to operate. DVI input can come from anywhere. Note that turning the projector off will lose whatever program is stored in memory.

Static image control programs must be tediously constructed by importing every image individually. If the project is in Structured Light mode, you will be asked to specify a threshold for converting it to a bitmap. Images can be either cycle at the specified frame rate, or manually stepped forward/backward.

APIs exist for writing more elaborate control programs, but they have not been confirmed by anyone in the lab. See Additional Features below for more information.

API

It is possible to create a batch file using commands the DLP Light Commander understands. Relevant documentation can be found at the following links:

• http://focus.ti.com/lit/an/dlpa014a/dlpa014a.pdf (broken for an unknown reason)

• http://focus.ti.com/lit/an/dlpa024a/dlpa024a.pdf

Sample code can be found by taking the following steps (on Windows XP):

1. Go to http://www.ti.com
2. Search for "DLP200app" in the keywords box
3. Click on "DLPC200 Configuration and support firmware
4. Click on "Reference Application Source Code for DLP 200 API"
5. Fill out a form for so-called "government approval" (turnaround was instant for me)
6. Install, then look at the installation directory ( "Program Files\Texas Instruments-DLP\ DLP LightCommander API Ref Apps\" )

Triggers

The projector has three jacks for analogue triggers that allow for synchronization with cameras or many other devices.

-- OliverSchneider - 27 Apr 2011

The DLP Light Commander is a projector that allows for extremely high frame rates, precise control over exposure time, colour balance of monochromatic light, and IR light. It is extremely finicky but very powerful. It runs on 32-bit operating systems only, and has only been tested with Windows XP. There are three different modes for display: Video, where it operates as a normal colour projector at up to 60 Hz; Structured Light, where it displays a series of static, monochromatic images read from onboard memory at rates of up to 5000Hz; and Real Time Structured Light, where it displays monochromatic images from a dynamic input (such as DVI) at up to 1440 Hz. In the software, Structured Light and Real Time Structured Light are differentiated only by source - they are both found under "Structured Light".

Hardware

Software Download and Installation

Go to the following link and click on support:

http://www.logicpd.com/products/development-kits/dlp-lightcommander-development-kit

You will need to sign up for an account. To register, you will need the following information:

• Part #: 1015647
• Serial #: 2910M00395

Download the control software and the software user manual, which should give you the following files respectively:

• 1017179A_DLP_LC_Control_SW_1-0-73-859.zip
• 1015703Rev2_DLP_LightCommander_SW_UM.pdf

Extract the zip file and install the software.

Turning the Projector On

1. Plug the projector into a power source, leave it turned off
2. Switch the projector to "Run" rather than "Park"
3. Plug the USB cable
4. Install the USB driver automatically (if necessary), or wait until the computer recognizes the projector
5. Start up the control software

Using the Control Software

Important: When changing whether a project is using one of the Structured Lights or Video, you must create a new project. The software fails to compile when you change this without creating a new project.

Video

Structured Light

Real-Time Structured Light

• If the projector is reading input from DVI and is not displaying correctly, try the following:
  1. Put the projector into "Park"
  2. Pull the HDMI end of the cable out of the projector
  3. Plug the HDMI cable back in
  4. Put the projector into "Run"

Additional Features

There are several additional features that have not been confirmed by a PSM lab member.

This page is a work in progress.

DLP Light Commander

The DLP Light Commander is a project with really, really fast refresh rates.

Overview

Installation & Start up

The Different Modes

Tips & Tricks