Rainbow Electronics AT89C5132 - Manual (Page 18)

18
AT8xC5132
4173A–8051–08/02
Program/Code
Memory
The AT89C5132 and AT83C5132 implement 64K Bytes of on-chip program/code mem-
ory. Figure 11 shows the split of internal and external program/code memory spaces
depending on the product.
The AT83C5132 product provides the internal program/code memory in ROM memory
while the AT89C5132 product provides it in Flash memory. These two products do not
allow external code memory execution.
The Flash memory increases EPROM and ROM functionality by in-circuit electrical era-
sure and programming. The high voltage needed for programming or erasing Flash cells
is generated on-chip using the standard V
DD
voltage, made possible by the internal
charge pump. Thus, the AT89C5132 can be programmed using only one voltage and
allows in application software programming. Hardware programming mode is also avail-
able using common programming tools.
The AT89C5132 implements an additional 4K Bytes of on-chip boot Flash memory pro-
vided in Flash memory. This boot memory is delivered programmed with a standard
bootloader software allowing In-System Programming (ISP). It also contains some
Application Programming Interfaces (API), allowing In Application Programming (IAP)
by using user’s own bootloader.
Figure 11. Program/Code Memory Organization
ROM Memory
Architecture As shown in Figure 12, the AT83C5132 ROM memory is composed of two spaces
detailed in the following section.
Figure 12. ROM Memory Architecture
4K Bytes
Boot Flash
FFFFh
F000h
0000h
64K Bytes
Code Flash
FFFFh
AT89C5132
0000h
64K Bytes
Code ROM
FFFFh
AT83C5132
F000h
FFFFh
64K Bytes
ROM Memory
0000h
User