Application Overview

The Palm-O-Scope application runs on a Palm-compatible PDA, and communicates with a BlackBox through the PDA's serial port. Palm-O-Scope is responsible for scaling and graphing the data that is received from the BlackBox.

Palm-O-Scope runs on any Palm compatible PDA with an RS-232 serial port. The application has been tested using Palm OS 3.5 and 3.5.1, though older versions of the Palm OS should work also. Communication with the BlackBox requires an RS-232 serial port, which is available on nearly all PDAs.  The speed of the PDA is not a signifcant factor in the performance of the Palm-O-Scope application. The presently available Palm-compatible PDAs all run at similar speeds, and will present similar performance. However, faster PDAs will be able to refresh the screen more quickly, providing a smoother display of waveforms that change their shape over time.

Palm-O-Scope was written entirely in C++.  An object oriented design was used throughout the application. This allowed development of the program to be broken into much smaller, simpler modules.  Also, it eliminated many issues related to having multiple developers working on the same project. Most importantly, C++ allowed very fast development of a complicated program, while maximizing the readability and maintainability of the source code.

Palm-O-Scope has three major components:

  1. BlackBox Manager
  2. Display Manager
  3. User Interface
The BlackBox Manager is the part of the application that interacts with the BlackBox. It handles all serial communications and related protocol handling, and is the source of data for the Display Manager. The Display Manager receives trace data (measurements) from the BlackBox Manager and displays them on the PDAs display. Finally, the User Interface is a small collection of controls that allow the user to select how the waveforms should be displayed.

Voltage-Per-Division Settings

10, 5, 2.5, 1, 0.5, 0.25, 0.1, 0.05, 0.025, 0.01 volts

Time Stretching Settings

x1, x2, x4, x8, x16

Sample Screen Shots

Sample waveform at 5V/division

Sample  waveform at 5V/division, zoomed in by two

Sample waveform at 0.25V/division, zoomed in by two

Sample waveform at 0.25V/division, zoomed in by four