AT89C51RC2-SLSUL Atmel, AT89C51RC2-SLSUL Datasheet - Page 17

• Manufacturer Part Number: AT89C51RC2-SLSUL
• Description: IC 8051 MCU FLASH 32K 44PLCC
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51RC2-SLSUL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 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: 1280 B
• Interface Type: UART, SPI
• Maximum Clock Frequency: 60 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Package: 44PLCC
• Device Core: 80C51
• Family Name: AT89
• Maximum Speed: 40 MHz
• For Use With: AT89OCD-01 - USB EMULATOR FOR AT8XC51 MCUAT89STK-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 6. Mode Switching Waveforms
4180E–8051–10/06
XTAL1
XTAL1:2
X2 Bit
CPU Clock
x1 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 Hardware Security Byte (HSB). 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
(Table 15) and SPIX2 bit in the CKCON1 register (see Table 16) allow a switch from
standard peripheral speed (12 clock periods per peripheral clock cycle) to fast periph-
eral speed (6 clock periods per peripheral clock cycle). These bits are active only in X2
mode.
F
OSC
X2 Mode
AT89C51RB2/RC2
X1 Mode
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