T89C51CC01 Atmel, T89C51CC01 Datasheet - Page 36

• Manufacturer Part Number: T89C51CC01
• Description: Enhanced 8-Bit Microcontroller
• Manufacturer: Atmel

Program/Code
Memory
36
T89C51CC01
The T89C51CC01 implement 32K Bytes of on-chip program/code memory. Figure 17
shows the partitioning of internal and external program/code memory spaces depending
on the product.
The Flash memory increases EPROM and ROM functionality by in-circuit electrical era-
sure and programming. Thanks to the internal charge pump, the high voltage needed for
programming or erasing Flash cells is generated on-chip using the standard VDD volt-
age. Thus, the Flash Memory can be programmed using only one voltage and allows In-
System-Programming commonly known as ISP. Hardware programming mode is also
available using specific programming tool.
Figure 17. Program/Code Memory Organization
Notes:
1. If the program executes exclusively from on-chip code memory (not from external
2. Default factory programmed parts come with maximum hardware protection. Execu-
memory), beware of executing code from the upper byte of on-chip memory (7FFFh)
and thereby disrupt I/O Ports 0 and 2 due to external prefetch. Fetching code con-
stant from this location does not affect Ports 0 and 2.
tion from external memory is not possible unless the Hardware Security Byte is
reprogrammed. See Table 27.
7FFFh
0000h
32K Bytes
internal
EA = 1
Flash
FFFFh
8000h
32K Bytes
memory
external
7FFFh
0000h
32K Bytes
external
memory
EA = 0
4129K–CAN–01/05