atmega32u4-16mu ATMEL Corporation, atmega32u4-16mu Datasheet - Page 278

• Manufacturer Part Number: atmega32u4-16mu
• Description: Atmega32u4 8-bit Avr Microcontroller With 32k Bytes Of Isp Flash And Usb Controller
• Manufacturer: ATMEL Corporation

22.5
22.5.1
22.5.2
278
Power modes
ATmega32U4
Idle mode
Power down
UESTAX.6
UESTAX.5
UEINTX.6
UEINTX.4
UEINTX.3
UEINTX.2
UEINTX.1
UEINTX.0
UNDERFI
NAKOUTI
OVERFI
RXOUTI
STALLEDI
RXSTPI
NAKINI
TXINI
Figure 22-10. USB Endpoint Interrupt vector sources
Each endpoint has 8 interrupts sources associated with flags, and each source can be enabled
or not to trigger the corresponding endpoint interrupt. If, for an endpoint, at least one of the
sources is enabled to trigger interrupt, the corresponding event(s) will make the program branch
to the USB Endpoint Interrupt vector. The user may determine the source (endpoint) of the inter-
rupt by reading the UEINT register, and then handle the event detected by polling the different
flags.
In this mode, the CPU core is halted (CPU clock stopped). The Idle mode is taken wether the
USB controller is running or not. The CPU “wakes up” on any USB interrupts.
In this mode, the oscillator is stopped and halts all the clocks (CPU and peripherals). The USB
controller “wakes up” when:
• the WAKEUPI interrupt is triggered
• the VBUSTI interrupt is triggered
UEIENX.7
UEIENX.6
UEIENX.4
UEIENX.3
UEIENX.2
UEIENX.1
UEIENX.0
RXOUTE
STALLEDE
FLERRE
TXSTPE
RXSTPE
NAKINE
TXINE
UEINT.X
Endpoint 0
EPINT
Endpoint 1
Endpoint 2
Endpoint 3
Endpoint 4
Endpoint 5
Endpoint 6
Interrupt Vector
USB Endpoint
7766A–AVR–03/08