ATMEGA6490-16AI Atmel, ATMEGA6490-16AI Datasheet - Page 195

• Manufacturer Part Number: ATMEGA6490-16AI
• Description: IC AVR MCU FLASH 64K 5V 100TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA6490-16AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 68
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• For Use With: ATSTK600-TQFP100 - STK600 SOCKET/ADAPTER 100-TQFPATSTK504 - STARTER KIT AVR EXP MOD 100P LCD
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

20. USI – Universal Serial Interface
20.1
20.2
2552K–AVR–04/11
Features
Overview
The Universal Serial Interface, or USI, provides the basic hardware resources needed for serial
communication. Combined with a minimum of control software, the USI allows significantly
higher transfer rates and uses less code space than solutions based on software only. Interrupts
are included to minimize the processor load. The main features of the USI are:
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A simplified block diagram of the USI is shown on Figure 20-1. For the actual placement of I/O
pins, refer to
CPU accessible I/O Registers, including I/O bits and I/O pins, are shown in bold. The device-
specific I/O Register and bit locations are listed in the
Figure 20-1. Universal Serial Interface, Block Diagram
The 8-bit Shift Register is directly accessible via the data bus and contains the incoming and
outgoing data. The register has no buffering so the data must be read as quickly as possible to
ensure that no data is lost. The most significant bit is connected to one of two output pins
depending of the wire mode configuration. A transparent latch is inserted between the Serial
Register Output and output pin, which delays the change of data output to the opposite clock
edge of the data input sampling. The serial input is always sampled from the Data Input (DI) pin
independent of the configuration.
Two-wire Synchronous Data Transfer (Master or Slave)
Three-wire Synchronous Data Transfer (Master or Slave)
Data Received Interrupt
Wake up from Idle Mode
In Two-wire Mode: Wake-up from All Sleep Modes, Including Power-down Mode
Two-wire Start Condition Detector with Interrupt Capability
“Pinout ATmega3290/6490” on page 2
USIDR
USICR
USISR
2
4-bit Counter
3
2
1
0
3
2
1
0
D Q
LE
ATmega329/3290/649/6490
[1]
TIM0 COMP
0
1
and
“Register Descriptions” on page
“Pinout ATmega329/649” on page
Two-wire Clock
Control Unit
CLOCK
HOLD
DO
DI/SDA
USCK/SCL
(Output only)
(Input/Open Drain)
(Input/Open Drain)
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3.