AT90USB64/128
22.19 Registers
22.19.1 USB device general registers
Bit
7
-
6
-
5
-
4
-
3
-
2
1
0
LSM
R/W
0
RMWKUP DETACH
UDCON
Read/Write
Initial Value
R
0
R
0
R
0
R
0
R
0
R/W
0
R/W
1
• 7-3 - Reserved
The value read from these bits is always 0. Do not set these bits.
• 2 - LSM - USB Device Low Speed Mode Selection
When configured USB is configured in device mode, this bit allows to select the USB the USB
Low Speed or Full Speed Mod.
Clear to select full speed mode (D+ internal pull-up will be activate with the ATTACH bit will be
set) .
Set to select low speed mode (D- internal pull-up will be activate with the ATTACH bit will be
set). This bit has no effect when the USB interface is configured in HOST mode.
• 1- RMWKUP - Remote Wake-up Bit
Set to send an “upstream-resume” to the host for a remote wake-up.
Cleared by hardware. Clearing by software has no effect.
See Section 22.11, page 273 for more details.
• 0 - DETACH - Detach Bit
Set to physically detach de device (disconnect internal pull-up on D+ or D-).
Clear to reconnect the device. See Section 22.10, page 272 for more details.
Bit
7
-
6
5
4
3
2
1
0
UPRSMI
EORSMI WAKEUPI EORSTI
SOFI
-
SUSPI
UDINT
Read/Write
Initial Value
0
0
0
0
0
0
0
0
• 7 - Reserved
The value read from this bits is always 0. Do not set this bit.
• 6 - UPRSMI - Upstream Resume Interrupt Flag
Set by hardware when the USB controller is sending a resume signal called “Upstream
Resume”. This triggers an USB interrupt if UPRSME is set.
Shall be cleared by software (USB clocks must be enabled before). Setting by software has no
effect.
• 5 - EORSMI - End Of Resume Interrupt Flag
Set by hardware when the USB controller detects a good “End Of Resume” signal initiated by
the host. This triggers an USB interrupt if EORSME is set.
281
7593A–AVR–02/06
ATMEL [ ATMEL ]
