1. PC Scope (a PC Compatible, PC-Based Oscilloscope) Moises Feliz and Thomas Neish EE 413 Spring 2005

2. Abstract Oscilloscopes play a very important role in the design & development of various electronic systems. The current market is flooded with a host of oscilloscopes, however there are very few that are affordable & user friendly. Our solution to this problem is to develop a PC based oscilloscope.

3. PC Scope Advantages Low cost. Ease of use. Compact design which makes it portable. Ideal for students, hobbyists, home use.

4. Project Objectives Measure AC and DC signals. Sample and digitize signals. Transmit data to PC for processing. Display signal with software.

5. Hardware Phase

6. Specifications Range of voltage measurement: 0 V to 500 V. Bandwidth: 0 to 100 kHz. Voltage scaling will be user selected on program. Sampled data will be transferred to PC through LPT parallel port. User Hardware Interface: “Visual Basic.”

7. Block Diagram Signal Range Selector ADC

8. Schematics

9. Breadboard Front-end Voltage Protection Dual 4:1 Multiplexer ADC D25 Parallel Port Connector

10. Software Phase

11. Parallel Port Interfacing To interface with the parallel port we used a driver called “INPOUT32.dll”.

12. INPOUT32 Driver Definition

13. Programming Range? x1X10 Read ADC Counter > 601 Increment Counter by 1 x100 RANGE CALC Function GRAPH STOP Button Pressed NOYES STOP PROGRAM YES NO

14. Problems and Accomplishments Software Issues 1.Graphing one pixel/per sample and redrawing grid slowed down communication. 2.Display updated graph every 1 ms. Solutions 1.Refresh display only when a change of voltage occurs. 2.Display updates every 100 ms.

15. UB-Scope Program Run/ Stop (UBScope Control) Data Port from LPT Scaling Selection

16. DEMONSTRATION

17. Time Line and Status

18. Questions? mfeliz@buffalo.edu tdneish@buffalo.edu