AT90USB647-MU Atmel, AT90USB647-MU Datasheet - Page 270

• Manufacturer Part Number: AT90USB647-MU
• Description: MCU, 8BIT, 64K FLASH, USB, 64QFN
• Manufacturer: Atmel

Specifications of AT90USB647-MU

• Controller Family/series: AT90
• No. Of I/o's: 48
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 16MHz
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 64KB
• Oscillator Type: External, Internal
• Package: 64QFN EP
• Device Core: AVR
• Family Name: AT90
• Maximum Speed: 20 MHz
• Ram Size: 4 KB
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 48
• Interface Type: SPI/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 4
• Lead Free Status / Rohs Status: Details

22.8
22.9
270
Suspend, Wake-up and Resume
Detach
AT90USB64/128
ADDEN is cleared by hardware:
When this bit is cleared, the default device address 00h is used.
After a period of 3 ms during which the USB line was inactive, the controller switches to the full-
speed mode and triggers (if enabled) the SUSPI (suspend) interrupt. The firmware may then set
the FRZCLK bit.
The CPU can also, depending on software architecture, enter in the idle mode to lower again the
power consumption.
There are two ways to recover from the “Suspend” mode:
There are no relationship between the SUSPI interrupt and the WAKEUPI interrupt: the WAKE-
UPI interrupt is triggered as soon as there are non-idle patterns on the data lines. Thus, the
WAKEUPI interrupt can occurs even if the controller is not in the “suspend” mode.
When the WAKEUPI interrupt is triggered, if the SUSPI interrupt bit was already set, it is cleared
by hardware.
When the SUSPI interrupt is triggered, if the WAKEUPI interrupt bit was already set, it is cleared
by hardware.
The reset value of the DETACH bit is 1.
It is possible to re-enumerate a device, simply by setting and clearing the DETACH bit.
Figure 22-3. Detach a device in Full-speed:
• after a power-up reset,
• when an USB reset is received,
• or when the macro is disabled (USBE cleared)
• First one is to clear the FRZCLK bit. This is possible if the CPU is not in the Idle mode.
• Second way, if the CPU is “idle”, is to enable the WAKEUPI interrupt (WAKEUPE set). Then,
• Setting DETACH will disconnect the pull-up on the D+ or D- pad (depending on full or low
as soon as an non-idle signal is seen by the controller, the WAKEUPI interrupt is triggered.
The firmware shall then clear the FRZCLK bit to restart the transfer.
speed mode selected). Then, clearing DETACH will connect the pull-up on the D+ or D- pad.
UVREF
EN=1
D +
D -
Detach, then
Attach
UVREF
EN=1
D +
D -
7593K–AVR–11/09