AT90USB646-MU Atmel, AT90USB646-MU Datasheet - Page 257

• Manufacturer Part Number: AT90USB646-MU
• Description: IC AVR MCU 64K 64QFN
• Manufacturer: Atmel
• Series: AVR® 90USBr

Specifications of AT90USB646-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART, USB, USB OTG
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 48
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VQFN Exposed Pad, 64-HVQFN, 64-SQFN, 64-DHVQFN
• Processor Series: 90USB
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, TWI, USART, USB
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 48
• Number Of Timers: 4
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Cpu Family: AT90
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Total Internal Ram Size: 4KB
• # I/os (max): 48
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 64
• Package Type: QFN EP
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATSTK525 - KIT STARTER FOR AT90USBAT90USBKEY2 - KIT DEMO FOR AT90USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: AT90USB646-16MU; AT90USB646-16MU

21.6.2
21.7
7593K–AVR–11/09
Memory management
Host mode
EPEN=1
ALLOC=1
When the USB interface is configured in host mode, internal Pull Down resistors are activated on
both UDP UDM lines and the interface detects the type of connected device.
The controller does only support the following memory allocation management.
The reservation of a Pipe or an Endpoint can only be made in the increasing order (Pipe/End-
point 0 to the last Pipe/Endpoint). The firmware shall thus configure them in the same order.
The reservation of a Pipe or an Endpoint “k
ware allocates the memory and inserts it between the Pipe/Endpoints “k
Pipe/Endpoint memory “slides” up and its data is lost. Note that the “k
point memory does not slide.
Clearing a Pipe enable (PEN) or an Endpoint enable (EPEN) does not clear either its ALLOC bit,
or its configuration (EPSIZE/PSIZE, EPBK/PBK). To free its memory, the firmware should clear
ALLOC. Then, the “k
and upper Pipe/Endpoint memory does not slide.
The following figure illustrates the allocation and reorganization of the USB memory in a typical
example:
Table 21-1.
Pipe/Endpoints
• First, Pipe/Endpoint 0 to Pipe/Endpoint 5 are configured, in the growing order. The memory
• Then, the Pipe/Endpoint 3 is disabled (EPEN=0), but its memory reservation is internally kept
• Its ALLOC bit is cleared: the Pipe/Endpoint 4 “slides” down, but the Pipe/Endpoint 5 does not
• Finally, if the firmware chooses to reconfigure the Pipe/Endpoint 3, with a bigger size. The
Free memory
of each is reserved in the DPRAM.
by the controller.
“slide”.
controller reserved the memory after the endpoint 2 memory and automatically “slide” the
Pipe/Endpoint 4. The Pipe/Endpoint 5 does not move and a memory conflict appear, in that
activation
5
4
3
2
1
0
Allocation and reorganization USB memory flow
i+1
” Pipe/Endpoint memory automatically “slides” down. Note that the “k
Pipe/Endpoint
Free memory
(ALLOC=1)
Disable
EPEN=0
5
4
2
1
0
i
” is done when its ALLOC bit is set. Then, the hard-
Free its memory
Free memory
Lost memory
(ALLOC=0)
5
4
2
1
0
AT90USB64/128
3 (bigger size)
Pipe/Endpoint
Free memory
Activatation
i+2
i-1
” and upper Pipe/End-
4
” and “k
2
1
0
5
i+1
”. The “k
Conflict
257
i+1
i+2
”
”