Rainbow Electronics AT89C5132 - Manual (Page 19)

19
AT8xC5132
4173A–8051–08/02
User Space This space is composed of a 64K Bytes ROM memory programmed during the manu-
facturing process. It contains the user’s application code.
Flash Memory
Architecture As shown in Figure 13 the AT89C5132 Flash memory is composed of four spaces
detailed in the following paragraphs.
Figure 13. Flash Memory Architecture
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 21)
divided in two separate nibbles see Table 21. The MSN contains the X2 mode configu-
ration 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.
FFFFh
64K Bytes
Flash Memory
0000h
Hardware Security
User
4K Bytes
Flash Memory
FFFFh
F000h
Boot
Extra Row