Rainbow Electronics AT89C5132 - Manual (Page 3)

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AT89C5132
4256A–USB–06/03
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 imple-
ments a USB protocol (see Section “Protocol”, page 10). 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 pro-
gram 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
bootloader. 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 par-
allel programmer devices, this area is called Lock bits.
Note: U: Unprogrammed = 1
P: Program = 0
Table 1. Configuration and Manufacturer Byte 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