AT90USB647-MU Atmel, AT90USB647-MU Datasheet - Page 282

• 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

22.18.2
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