ATmega16U2 Atmel Corporation, ATmega16U2 Datasheet - Page 208

• 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

21.17 Interrupts
7799D–AVR–11/10
It is not possible to have overflow error during IN stage, in the CPU side, since the CPU should
write only if the bank is ready to access data (TXINI=1 or RWAL=1).
The next figure shows all the interrupts sources:
Figure 21-4. USB Device Controller Interrupt System
There are 2 kind of interrupts: processing (i.e. their generation are part of the normal processing)
and exception (errors).
Processing interrupts are generated when:
Exception Interrupts are generated when:
• Upstream resume( UPRSMI )
• End of resume( EORSMI )
• Wake up( WAKEUPI )
• End of reset (Speed Initialization)( EORSTI )
• Start of frame( SOFI , if FNCERR=0)
• Suspend detected after 3 ms of inactivity( SUSPI )
• CRC error in frame number of SOF( SOFI , FNCERR=1)
EORSMI
UPRSMI
UDINT.6
UDINT.5
WAKEUPI
UDINT.4
EORSTI
UDINT.3
UDINT.2
UDINT.0
SUSPI
SOFI
UPRSME
EORSME
UDIEN.6
UDIEN.5
WAKEUPE
UDIEN.4
EORSTE
UDIEN.3
UDIEN.2
UDIEN.0
SUSPE
SOFE
ATmega8U2/16U2/32U2
USB Device
Interrupt
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