For IN transfer, it indicates the Toggle that will be used for the next packet to be sent. This is not
relative to the current bank.
• 1-0 - NBUSYBK1:0 - Busy Bank Flag
Set by hardware to indicate the number of busy bank.
For IN endpoint, it indicates the number of busy bank(s), filled by the user, ready for IN transfer.
For OUT endpoint, it indicates the number of busy bank(s) filled by OUT transaction from the
host.
00b All banks are free
01b 1 busy bank
10b 2 busy banks
11b Reserved.
Bit
7
-
6
-
5
-
4
-
3
-
2
1
0
CTRLDIR
CURRBK1:0
UESTA1X
Read/Write
Initial Value
R
0
R
0
R
0
R
0
R
0
R
0
R
R
0
0
• 7-3 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 2 - CTRLDIR - Control Direction (Flag, and bit for debug purpose)
Set by hardware after a SETUP packet, and gives the direction of the following packet:
- 1 for IN endpoint
- 0 for OUT endpoint.
Can not be set or cleared by software.
• 1-0 - CURRBK1:0 - Current Bank (all endpoints except Control endpoint) Flag
Set by hardware to indicate the number of the current bank:
00b Bank0
01b Bank1
1xb Reserved.
Can not be set or cleared by software.
Bit
7
FIFOCON
R/W
6
NAKINI
R/W
0
5
4
3
RXSTPI
R/W
0
2
1
0
TXINI
R/W
0
RWAL NAKOUTI
RXOUTI STALLEDI
UEINTX
Read/Write
Initial Value
R/W
0
R/W
0
R/W
0
R/W
0
0
• 7 - FIFOCON - FIFO Control Bit
For OUT and SETUP Endpoint:
288
AT90USB64/128
7593A–AVR–02/06
ATMEL [ ATMEL ]
