AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 66

• 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

Reading commands
FLASH
CONFIGURATION
SECURITY
BOOTLOADER
SIGNATURE
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AT89C51RE2
The reading command is supported by the following areas:
Table 42. Memory space & Select page
The reading command on the Flash memory can be done from address 000h to 1FFFFh. The
read operation is only possible if the HSB (Hardware Security Byte) has a security level lower
than or equal to ‘2’ (FLB2.0 = ‘110’)
Table 43. Flash Read Authorization Summary
The CONFIGURATION family can always be read.
The SECURITY family can always be read.
All the field from the BOOTLOARED family can be read from the bootloader. Each bootloader
information shall be read unitary. Accesses must be done byte per byte according to the address
definition
All the field from the SIGNATURE family can be read from the bootloader. Each signature infor-
mation shall be read unitary. Accesses must be done byte per byte according to the address
definition
FLASH
SECURITY
CONFIGURATION
BOOTLOADER
SIGNATURE
Read
Memory/Information Family
Command
Allowed
111
Allowed
110
Security level (HSB)
need security level check
Comments/Restriction
FLB2:0
Forbidden
101
7663E–8051–10/08
Forbidden
011