AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 52
AT89C51RE2
Manufacturer Part Number
AT89C51RE2
Description
Manufacturer
Atmel Corporation
Specifications of AT89C51RE2
Flash (kbytes)
128 Kbytes
Max. Operating Frequency
60 MHz
Cpu
8051-12C
Max I/o Pins
34
Spi
1
Uart
2
Sram (kbytes)
8.25
Self Program Memory
API
Operating Voltage (vcc)
2.7 to 5.5
Timers
4
Isp
UART/OCD
Watchdog
Yes
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
AT89C51RE2-RLTEM
Manufacturer:
BPS
Quantity:
30 000
Company:
Part Number:
AT89C51RE2-RLTUM
Manufacturer:
MSC
Quantity:
1 560
Company:
Part Number:
AT89C51RE2-SLRUM
Manufacturer:
Atmel
Quantity:
759
Company:
Part Number:
AT89C51RE2-SLSUM
Manufacturer:
HONEYWELL
Quantity:
101
Company:
Part Number:
AT89C51RE2-UM
Manufacturer:
XILINX
Quantity:
101
Flash Protection from Parallel Programming
52
AT89C51RE2
The three lock bits in Hardware Security Byte (see "In-System Programming" section) are pro-
grammed according to Table 32 provide different level of protection for the on-chip flash memory
FM0.
They are set by default to level 4
Table 32. Program Lock Bit FLB2-0
Program Lock bits
U: unprogrammed
P: programmed
WARNING: Security level 2 and 3 should only be programmed after verification.
Security
level
1
2
3
4
Program Lock Bits
FLB0
U
U
U
P
FLB1
U
U
P
U
FLB2
U
U
U
P
Protection Description
No program lock features enabled.
MOVC instruction executed from external program memory are disabled from
fetching code bytes from internal memory, EA is sampled and latched on reset,
and further parallel programming of the Flash is disabled.
ISP allows only flash verification (no write operations are allowed) but IAP from
internal code still allowed.
Same as 2, also verify through parallel programming interface is disabled and
ISP read operation not allowed.
Same as 3, also external execution is disabled (external bank not accessible)
7663E–8051–10/08