ATmega16U2 Atmel Corporation, ATmega16U2 Datasheet - Page 190

• Manufacturer Part Number: ATmega16U2
• Manufacturer: Atmel Corporation

Specifications of ATmega16U2

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 22
• Ext Interrupts: 21
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 5
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

20.4.3
7799D–AVR–11/10
Interrupts
When the USB controller is in reset state:
After setting USBE, the USB Controller enters in the Device state.
The USB Controller can at any time be reset by clearing USBE.
Two interrupts vectors are assigned to the USB controller.
Figure 20-8. USB Interrupt System
The USB module distinguishes between USB General events and USB Endpoints events.
Figure 20-9. USB General interrupt vector sources
The WAKEUP interrupt allows device wake-up from power-down mode, and is an asynchronous
interrupt, triggering each time a state change is detected on the data lines. The other interrupts
are synchronous and will be detected only if the USB clock is enabled (FRZCLK bit set).
• USBE is not set
• the USB controller clock is stopped in order to minimize the power consumption (FRZCLK=1)
• the USB controller is disabled
• USB is in the suspend mode
• the Device USB controllers internal state is reset
• The DPACC bit and the DPADD10:0 field can be set by software. The DPRAM is not cleared.
• The SPDCONF bits can be set by software
UPRSMI
UDINT.6
EORSMI
UDINT.5
WAKEUPI
UDINT.4
UDINT.3
UDINT.2
UDINT.0
EORSTI
SUSPI
SOFI
Endpoint
Interrupt
USB Device
Interrupt
UPRSME
EORSME
WAKEUPE
EORSTE
UDIEN.6
UDIEN.5
UDIEN.4
UDIEN.3
UDIEN.2
UDIEN.0
SUSPE
SOFE
ATmega8U2/16U2/32U2
Asynchronous Interrupt source
(allows the CPU to wake up from power down mode)
Interrupt Vector
USB General
USB Endpoint/Pipe
Interrupt Vector
Interrupt Vector
USB General
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