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A/T89C51AC2 UART Bootloader

4231C–CAN–03/05

Functional

Description

The A/T89C51AC2 Bootloader facilitates In-System Programming and In-Application

Programming.

In-System Programming

Capability

In-System Programming (ISP) allows the user to program or reprogram a microcontrol-

ler’s on-chip Flash memory without removing it from the system and without the need of

a pre-programmed application.

The UART bootloader can manage a communication with a host through the serial net-

work. It can also access and perform requested operations on the on-chip Flash

memory.

In-Application

Programming or Self-

programming Capability

In-Application Programming (IAP) allows the reprogramming of the microcontroller on-

chip Flash memory without removing it from the system and while the embedded appli-

cation is running.

The UART bootloader contains some Application Programming Interface routines

named API routines allowing IAP by using the user’s firmware.

Block Diagram

This section describes the different parts of the bootloader. The figure below shows the

on-chip bootloader and IAP processes.

Figure 1. Bootloader Process Description

ISP Communication

Management

User

Application

UART Protocol

Communication

Management

Flash

Memory

External Host Via the

Flash Memory

IAP

Management

User Call

On-chip