Datasheet

17
AT89C5132
4173C–USB–07/04
User Space This space is composed of a 64K Bytes Flash memory organized in 512 pages of 128
Bytes. It contains the user’s application code. This space can be read or written by both
software and hardware modes.
Boot Space This space is composed of a 4K Bytes Flash memory. It contains the bootloader for In-
System Programming and the routines for In-System Application Programming.
This space can only be read or written by hardware mode using a parallel programming
tool.
Hardware Security Space This space is composed of one byte: the Hardware Security Byte (HSB see Table 7)
divided in two separate nibbles see Table 7. The MSN contains the X2 mode configura-
tion bit and the Boot Loader Jump Bit as detailed in section “Boot Memory Execution”
and can be written by software while the LSN contains the lock system level to protect
the memory content against piracy as detailed in section “Hardware Security System”
and can only be written by hardware.
Extra Row Space This space is composed of two Bytes:
• The Software Boot Vector (SBV see Table 8).
This byte is used by the software bootloader to build the boot address.
• The Software Security Byte (SSB see Figure ).
This byte is used to lock the execution of some bootloader commands.
Hardware Security
System
The AT89C5132 implements three lock Bits LB2:0 in the LSN of HSB (see Table 7) pro-
viding three levels of security for user’s program as described in Table 7 while the
AT83C51SND1C is always set in read disabled mode.
• Level 0 is the level of an erased part and does not enable any security feature.
• Level 1 locks the hardware programming of both user and boot memories.
• Level 2 locks hardware verifying of both user and boot memories.
• Level 3 locks the external execution.
Notes: 1. U means unprogrammed, P means programmed and X means don’t care (pro-
grammed or unprogrammed).
2. LB2 is not implemented in the AT89C5132 products.
3. AT89C5132 products are delivered with third level programmed to ensure that the
code programmed by software using ISP or user’s bootloader is secured from any
hardware piracy.
Table 5. Lock Bit Features
(1)
Level LB2
(2)
LB1 LB0
Internal
Execution
External
Execution
Hardware
Verifying
Hardware
Programming
Software
Programming
0 U U U Enable Enable Enable Enable Enable
1 U U P Enable Enable Enable Disable Enable
2 U P X Enable Enable Disable Disable Enable
3
(3)
P X X Enable Disable Disable Disable Enable