AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 65

• Manufacturer Part Number: AT89C51RE2
• 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

Blank Checking
commands
FLASH
7663E–8051–10/08
The blank checking command is supported by the following areas
Table 40. Memory space & Erase
Nothing is done on the other areas.
The first not erased address is returned if the blank check is failed.
The blank checking command on the Flash memory can be done from address 0000h to
1FFFFh.
The blank check operation is only possible if the HSB (Hardware Security Byte) has a security
level lower than or equal to ‘2’ (FLB2.0 = ‘110’)
Table 41. Flash Blank check Authorization Summary
FLASH
Blank Check
Memory/Information Family
Command
Allowed
111
Allowed
110
Security level (HSB)
need security level check
Comments/Restriction
FLB2:0
Forbidden
AT89C51RE2
101
Forbidden
011
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