User manual

MPLAB

ICD 3 IN-CIRCUIT

DEBUGGER USER’S GUIDE

Chapter 2. Theory of Operation

2.1 INTRODUCTION

A simplified description of how the MPLAB ICD 3 in-circuit debugger system works is

provided here. It is intended to provide enough information so a target board can be

designed that is compatible with the debugger for both emulation and programming

operations. The basic theory of in-circuit emulation and programming is described so

that problems, if encountered, are quickly resolved.

• MPLAB ICD 3 In-Circuit Debugger vs. MPLAB ICE 2000/4000 In-Circuit

Emulators

• MPLAB ICD 3 In-Circuit Debugger vs. MPLAB ICD 2 Debugger

• Debugger To Target Communication

• Communication Connections

• Debugging with the Debugger

• Requirements For Debugging

• Programming with the Debugger

• Resources Used by the Debugger

2.2 MPLAB ICD 3 IN-CIRCUIT DEBUGGER VS. MPLAB ICE 2000/4000

IN-CIRCUIT EMULATORS

The MPLAB ICD 3 in-circuit debugger system is a next generation In-Circuit Debugger

(ICD) system. It differs from classical in-circuit emulator systems (e.g., MPLAB ICE

2000/4000) in a single, but important way: the production device and emulation device

are the same.

This is a great benefit since differences (errata) between the production silicon and

emulation silicon are eliminated. Additionally, as devices continue to operate at faster

speeds, traditional emulator systems present bottlenecks caused by internal busses

that must be carried off-chip to external memories and cannot offer full speed

emulation.

Another significant benefit is that there is no lead time between production silicon and

emulation silicon. Further, a problem encountered on a production board can be easily

debugged without having to install transition sockets and dealing with complicated

cabling systems and setups to have access to the application.

2.3 MPLAB ICD 3 IN-CIRCUIT DEBUGGER VS. MPLAB ICD 2 DEBUGGER

The MPLAB ICD 3 in-circuit debugger system is similar in function to the MPLAB ICD

2 in-circuit debugger system, but surpasses it in speed and functionality. The MPLAB

ICD 3 also:

• Features USB high speed

• Is USB powered

• Is a hardware accelerator

• Provides a programmable voltage power supply

• Eliminates the RS-232 port

• Includes a diagnostic self-test interface board