AT89C51ID2 Atmel Corporation, AT89C51ID2 Datasheet - Page 80

• Manufacturer Part Number: AT89C51ID2
• Manufacturer: Atmel Corporation

Specifications of AT89C51ID2

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Sram (kbytes): 2
• Eeprom (bytes): 2048
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART
• Watchdog: Yes

2-wire Interface (TWI)
4289C–8051–11/05
This section describes the 2-wire interface. The 2-wire bus is a bi-directional 2-wire
serial communication standard. It is designed primarily for simple but efficient integrated
circuit (IC) control. The system is comprised of two lines, SCL (Serial Clock) and SDA
(Serial Data) that carry information between the ICs connected to them. The serial data
transfer is limited to 400 Kbit/s in standard mode. Various communication configuration
can be designed using this bus. Figure 29 shows a typical 2-wire bus configuration. All
the devices connected to the bus can be master and slave.
Figure 29. 2-wire Bus Configuration
SCL
SDA
device1
device2
device3
...
deviceN
AT89C51ID2
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