AT89C51RE2-SLRUM Atmel, AT89C51RE2-SLRUM Datasheet - Page 14

• Manufacturer Part Number: AT89C51RE2-SLRUM
• Description: MCU 8051 128K FLASH 44-PLCC
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51RE2-SLRUM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 60MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-PLCC
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 8 KB
• Interface Type: UART, SPI
• Maximum Clock Frequency: 60 MHz
• Number Of Programmable I/os: 34
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89OCD-01
• For Use With: AT89STK-11 - KIT STARTER FOR AT89C51RX2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details

Figure 3. Mode Switching Waveforms
14
AT89C51RE2
XTAL1
XTAL1:2
X2 bit
CPU clock
STD Mode
The X2 bit in the CKCON0 register (see Table 15) allows a switch from 12 clock periods per
instruction to 6 clock periods and vice versa. At reset, the speed is set according to X2 bit of the
Fuse Configuration Byte (FCB). By default, Standard mode is active. Setting the X2 bit activates
the X2 feature (X2 mode).
The T0X2, T1X2, T2X2, UartX2, PcaX2, and WdX2 bits in the CKCON0 register (See Table 15.)
and SPIX2 bit in the CKCON1 register (see Table 16) allows a switch from standard peripheral
speed (12 clock periods per peripheral clock cycle) to fast peripheral speed (6 clock periods per
peripheral clock cycle). These bits are active only in X2 mode.
F
X2 Mode
OSC
STD Mode
7663E–8051–10/08