AT89C51RC2-3CSIM datasheet(97/127 Pages) ATMEL

97 / 127 page

AT89C51RB2/RC2

4180C–8051–12/03

Full Chip Erase

The ISP command "Full Chip Erase" erases all User Flash memory (fills with FFh) and

sets some Bytes used by the bootloader at their default values:

•

BSB = FFh

•

SBV = FCh

•

SSB = FFh and finally erase the Software Security Bits

The Full Chip Erase does not affect the bootloader.

Checksum Error

When a checksum error is detected send ‘X’ followed with CR&LF.

Flow Description

Overview

An initialization step must be performed after each Reset. After microcontroller reset,

the bootloader waits for an autobaud sequence ( see section ‘autobaud performance’).

When the communication is initialized the protocol depends on the record type

requested by the host.

FLIP, a software utility to implement ISP programming with a PC, is available from the

Atmel the web site.

Communication Initialization

The host initializes the communication by sending a ’U’ character to help the bootloader

to compute the baudrate (autobaud).

Figure 40. Initialization

Host

Bootloader

"U"

Performs Autobaud

Init Communication

If (not received "U")

"U"

Communication Opened

Else

Sends Back ‘U’ Character

AT89C51RC2-3CSIM Datasheet(PDF) 97 Page - ATMEL Corporation