AT89C51IC2-RLTIL Atmel, AT89C51IC2-RLTIL Datasheet - Page 14

• Manufacturer Part Number: AT89C51IC2-RLTIL
• Description: IC 8051 MCU FLASH 32K 44VQFP
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51IC2-RLTIL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 34
• 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-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

Oscillators
Overview
Registers
14
AT89C51IC2
Two oscillators are available for CPU:
•
•
Several operating modes are available and programmable by software:
•
•
In order to optimize the power consumption and the execution time needed for a specific
task, an internal prescaler feature has been implemented between the selected oscilla-
tor and the CPU.
Table 14. CKSEL Register
CKSEL - Clock Selection Register (85h)
Reset Value = 0000 000’HSB.OSC’b (see Hardware Security Byte (HSB) Table 84)
Not bit addressable
Number
OSCA used for high frequency: Up to 48 MHz @5V +/- 10%
OSCB used for low frequency: 32.768 kHz
to switch OSCA to OSCB and vice-versa
to stop OSCA or OSCB to reduce consumption
Bit
7
-
7
6
5
4
3
2
1
0
Mnemonic Description
CKS
Bit
6
-
-
-
-
-
-
-
-
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
CPU Oscillator Select Bit: (CKS)
Cleared, CPU and peripherals connected to OSCB
Set, CPU and peripherals connected to OSCA
Programmed by hardware after a Power-up regarding Hardware Security Byte
(HSB).HSB.OSC (Default setting, OSCA selected)
5
-
4
-
3
-
2
-
1
-
4301D–8051–02/08
CKS
0