EE396: PDA

Alex Zamora

Project Overview

• Intend to build a touch-screen PDA that can read and write files.

• Main purpose: To have an organized non-paper based notebook for taking class notes.

Idealistic Origins

• To have a 8.5 x 11 inch display• To use Electronic Paper Display• To Create Motherboard from Scratch• To have USB storage• To use an EMR touch-screen• To have internet Connectivity

Tragic Reality

• 8.5 x 11 inch screens are too expensive– Settling for 7.8 inch (diagonal) screen

• EPD is too expensive– Settling for LCD

• Using Prefabricated Motherboard– This is the smart thing to do

• Using Resistive Panel Touch-screen– Found a Package Deal

…Reality Continued

• Will use USB storage– External Flash Drive

• Internet Connectivity Is Still a Possibility– Not a priority

Processing-The Gumstix Way

• Using Gumstix’s Connex 400xm– 400MHz (Intel XScale® PXA255)– 16 MB RAM– 60 pin I/O connector– 92 pin Bus Header

• Using Gumstix’s Breakout-gs– USB

Gumstix Advantages

• Linux OS preinstalled– USB drivers– Familiar Programming environment

• Many types of Expansion Boards– WIFI– Ethernet– USB

Display

• Panasonic EDMGRB8KJF– Color LCD 640 x3(RGB)x480 pixels– Passive Matrix (slower than Active) – 7.8 inch (measured diagonal)– LCD Active Area: 118.06 x 157.42 mm– 70Hz Frame Rate

Display Gumstix Interface

Touch-Screen

• DynaPro four wire resistive TTP– Graded resistance in X and Y directions– Screen returns voltage depending on position– Use ADC and calibrate manually• There is a linear dependence

Next Semester

• Build it• Program it• Flaunt it

ANY QUESTIONS?

• PS: • Website = www2.hawaii.edu/~azamora/projects