AT89S52-24JU Atmel, AT89S52-24JU Datasheet - Page 4

• Manufacturer Part Number: AT89S52-24JU
• Description: IC MCU 8K FLASH 24MHZ 44-PLCC
• Manufacturer: Atmel
• Series: 89Sr

Specifications of AT89S52-24JU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 24MHz
• Connectivity: UART/USART
• Peripherals: WDT
• Number Of I /o: 32
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-PLCC
• Package: 44PLCC
• Device Core: 8051
• Family Name: 89S
• Maximum Speed: 24 MHz
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 32
• Interface Type: UART
• Number Of Timers: 3
• Processor Series: AT89x
• Core: 8051
• Data Ram Size: 256 B
• Maximum Clock Frequency: 33 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89ISP
• Minimum Operating Temperature: - 40 C
• Eeprom Memory: 0 Bytes
• Input Output: 32
• Interface: UART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin PLCC
• Programmable Memory: 8K Bytes
• Timers: 3-16-bit
• Voltage, Range: 4-5.5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

4. Pin Description
4.1
4.2
4.3
4.4
4.5
4
VCC
GND
Port 0
Port 1
Port 2
AT89S52
Supply voltage.
Ground.
Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight TTL
inputs. When 1s are written to port 0 pins, the pins can be used as high-impedance inputs.
Port 0 can also be configured to be the multiplexed low-order address/data bus during accesses
to external program and data memory. In this mode, P0 has internal pull-ups.
Port 0 also receives the code bytes during Flash programming and outputs the code bytes dur-
ing program verification. External pull-ups are required during program verification.
Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 output buffers can
sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the inter-
nal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low
will source current (I
In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count input
(P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX), respectively, as shown in the follow-
ing table.
Port 1 also receives the low-order address bytes during Flash programming and verification.
Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 2 output buffers can
sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by the inter-
nal pull-ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low
will source current (I
Port 2 emits the high-order address byte during fetches from external program memory and dur-
ing accesses to external data memory that use 16-bit addresses (MOVX @ DPTR). In this
application, Port 2 uses strong internal pull-ups when emitting 1s. During accesses to external
data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special
Function Register.
Port 2 also receives the high-order address bits and some control signals during Flash program-
ming and verification.
Port Pin
P1.0
P1.1
P1.5
P1.6
P1.7
Alternate Functions
T2 (external count input to Timer/Counter 2), clock-out
T2EX (Timer/Counter 2 capture/reload trigger and direction control)
MOSI (used for In-System Programming)
MISO (used for In-System Programming)
SCK (used for In-System Programming)
IL
IL
) because of the internal pull-ups.
) because of the internal pull-ups.
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