AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 30

• 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

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AT89C51RE2
When EA=0, the on-chip flash memory is disabled and the MCU core can address only up to
64kByte of external memory (none of the on-chip flash memory FM0 banks or RM0 can be
mapped and executed).
Figure 11. Program/Code Memory Organization EA=0
FFFFh
Logical MCU
Address
0000h
Common
64K
External Physical Memory
Address
0FFFFh
00000h
On-Chip flash code memory
External code memory
7663E–8051–10/08