3

4256B–USB–03/06

AT89C5132

ISP Communication

Management

The purpose of this process is to manage the communication and its protocol between the on-

chip bootloader and an external device (host). The on-chip bootloader implements a USB proto-

col (see Section “Protocol”, page 12). This process translates serial communication frames

(USB) into Flash memory accesses (read, write, erase...).

User Call Management

Several Application Program Interface (API) calls are available to the application program to

selectively erase and program Flash pages. All calls are made through a common interface (API

calls) included in the bootloader. The purpose of this process is to translate the application

request into internal Flash memory operations.

Flash Memory

Management

This process manages low level accesses to the Flash memory (performs read and write

accesses).

Bootloader Configuration

Configuration and

Manufacturer

Information

The following table lists Configuration and Manufacturer byte information used by the boot-

loader. This information can be accessed through a set of API or ISP commands.

Mapping and Default

Value of Hardware

Security Byte

The 4 MSB of the Hardware Byte can be read/written by software (this area is called Fuse bits).

The 4 LSB can only be read by software and written by hardware using parallel programmer

devices, this area is called Lock bits.

Note:

U: Unprogrammed = 1

P: Programmed = 0

Table 1. Configuration and Manufacturer Information

Mnemonic

Description

Default Value

BSB

Boot Status Byte

FFh

SBV

Software Boot Vector

FOh

SSB

Software Security Byte

FFh

EB

Extra Byte

FFh

Manufacturer

58h

Id1: Family Code

D7h

Id2: Product Name

F7h

Id3: Product Revision

DFh

Table 2. Hardware Byte Information

Bit Position

Mnemonic

Default Value

Description

7

X2B

U

To start in x1 mode

6

BLJB

P

To map the boot area in code area between F000h-FFFFh

5

–

U

4

–

U

3

reserved

U

2

LB2

P

To lock the chip (see datasheet)

1

LB1

U

0

LB0

U