ATmega16U2 Atmel Corporation, ATmega16U2 Datasheet - Page 194

• 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

20.8
20.9
7799D–AVR–11/10
D+/D- Read/write
USB Software Operating modes
Moreover, the pad can also be put in the Idle mode if the DETACH bit is set. It come back in the
Active mode when the DETACH bit is cleared.
The level of D+ and D- can be read and written using the UPOE register. The USB controller has
to be enabled to write a value. For read operation, the USB controller can be enabled or
disabled.
Depending on the USB operating mode, the software should perform some of the following
operations:
Power On the USB interface
Power Off the USB interface
Suspending the USB interface
• Configure PLL interface
• Enable PLL
• Check PLL lock
• Enable USB interface
• Configure USB interface (USB Endpoint 0 configuration)
• Attach USB device
• Detach USB device
• Disable USB interface
• Disable PLL
• Clear Suspend Bit
• Set USB suspend clock
• Disable PLL
SUSPI
WAKEUPI
PAD status
Active
Suspend detected = USB pad power down
Resume = USB pad wake-up
Power Down
ATmega8U2/16U2/32U2
Clear Suspend by software
Clear Resume by software
Active
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