AT89C51RD2 Atmel Corporation, AT89C51RD2 Datasheet - Page 20

• Manufacturer Part Number: AT89C51RD2
• Manufacturer: Atmel Corporation

Specifications of AT89C51RD2

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Uart: 1
• Sram (kbytes): 2
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART
• Watchdog: Yes

20
AT89C51RD2/ED2
Reset Value = XXXX XXX0b
Not bit addressable
Number
Bit
2
1
0
Mnemonic
SPIX2
Bit
-
-
Description
Reserved
Reserved
SPI (This control bit is validated when the CPU clock X2 is set; when X2 is low, this bit
has no effect).
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
4235K–8051–05/08