AT90USB646-MUR Atmel, AT90USB646-MUR Datasheet - Page 282

• Manufacturer Part Number: AT90USB646-MUR
• Description: MCU AVR 64K FLASH 16MHZ 64QFN
• Manufacturer: Atmel
• Series: AVR® 90USBr

Specifications of AT90USB646-MUR

• 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
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, UART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 48
• Number Of Timers: 4
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

22.18.2
282
AT90USB64/128
USB device endpoint registers
• 7-5 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 4 - FNCERR -Frame Number CRC Error Flag
Set by hardware when a corrupted Frame Number in start of frame packet is received.
This bit and the SOFI interrupt are updated at the same time.
• 3-0 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 7-3 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 2-0 - EPNUM2:0 Endpoint Number Bits
Load by software to select the number of the endpoint which shall be accessed by the CPU. See
Section 22.5, page 268 for more details.
EPNUM = 111b is forbidden.
• 7 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 6-0 - EPRST6:0 - Endpoint FIFO Reset Bits
Set to reset the selected endpoint FIFO prior to any other operation, upon hardware reset or
when an USB bus reset has been received. See Section 22.3, page 267 for more information
Then, clear by software to complete the reset operation and start using the endpoint.
Bit
Read/Write
Initial Value
Bit
Read/Write
Initial Value
Bit
Read/W
rite
Initial
Value
7
0
-
R
7
R
0
7
0
-
-
EPRST6
6
0
-
R/W
R
6
0
6
0
-
EPRST5
5
0
-
R/W
R
5
0
5
0
-
FNCERR
EPRST4
R
4
0
R/W
R
4
0
4
0
-
EPRST3
R/W
3
0
-
R
3
0
3
0
-
EPRST2
R/W
R/W
2
0
-
2
0
2
0
EPNUM2:0
EPRST1
R/W
R/W
1
0
-
1
0
1
0
EPRST0
R/W
R/W
0
0
7593K–AVR–11/09
-
0
0
0
0
UDMFN
UENUM
UERST