AT89C51ID2-SLSIM Atmel, AT89C51ID2-SLSIM Datasheet - Page 120

• Manufacturer Part Number: AT89C51ID2-SLSIM
• Description: C51ID2 64KF TWI 32KHZ PLCC44 3-5.5V IND.
• Manufacturer: Atmel

Flash Memory Status
Figure 45. Flash memory possible contents
Memory Organization
4289C–8051–11/05
FFFFh
0000h
Default
Virgin
After ISP
Application
Table 93. Program Lock bits of the SSB
Note:
AT89C51ID2 parts are delivered in standard with the ISP rom bootloader.
After ISP or parallel programming, the possible contents of the Flash memory are sum-
marized on the figure below:
When the EA pin high, the processor fetches instructions from internal program Flash. .
If the EA pin is tied low, all program memory fetches are from external memory.
Security
level
Program Lock Bits
1
2
3
U: unprogrammed or "one" level.
P: programmed or "zero" level.
X: do not care
WARNING: Security level 2 and 3 should only be programmed after Flash and code
verification.
LB0
U
P
X
Dedicated
ISP
After ISP
application
Virgin
LB1
or
U
U
P
No program lock features enabled.
ISP programming of the Flash is disabled.
Same as 2, also verify through ISP programming interface is disabled.
After parallel
programming
Application
Protection description
After parallel
programming
Dedicated
ISP
application
Virgin
or
AT89C51ID2
After parallel
programming
application
Virgin
or
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