252
8331B–AVR–03/12
Atmel AVR XMEGA AU
• Bit 5 – BUSERRIE: Bus Error Interrupt Enable
Setting this bit will enable the interrupt for the following three bus error events:
1.
Isochronous CRC Error:
An interrupt will be generated for the conditions that set the
CRC interrupt flag (CRCIF) in the INTFLAGSACLR/SET register during isochronous
transfers.
2.
Underflow
: An interrupt will be generated for the conditions that set the undeflow inter-
rupt flag (UNFIF) in the INTFLAGSACLR/SET register.
3.
Overflow
: An interrupt will be generated for the conditions that set the overflow interrupt
flag (OVFIF) in the INTFLAGSACLR/SET register.
The INTLVL bits must be nonzero for the interrupts to be generated.
• Bit 4 – STALLIE: STALL Interrupt Enable
Setting this bit enables the STALL interrupt for the conditions that set the stall interrupt flag
(STALLIF) in the INTFLAGSACLR/SET register. The INTLVL bits must be nonzero for the inter-
rupts to be generated.
• Bit 3:2 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to zero when this register is written.
• Bit 1:0 – INTLVL[1:0]: Interrupt Level
These bits enable the USB interrupts and select the interrupt level, as described in
and Programmable Multilevel Interrupt Controller” on page 134
. In addition, each USB interrupt
source must be separately enabled.
20.13.10 INTCTRLB – Interrupt Control register B
• Bit 7:2 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to zero when this register is written.
• Bit 1 – TRNIE: Transaction Complete Interrupt Enable
Setting this bit enables the transaction complete interrupt for IN and OUT transactions. The
INTLVL bits must be nonzero for interrupts to be generated.
• Bit 0 – SETUPIE: SETUP Transaction Complete Interrupt Enable
Setting this bit enables the SETUP Transaction Complete Interrupt for SETUP transactions. The
INTLVL bits must be non-zero for the interrupts to be generated.
20.13.11 INTFLAGSACLR/ INTFLAGSASET – Clear/ Set Interrupt Flag register A
This register is mapped into two I/O memory locations, one for clearing (INTFLAGSACLR) and
one for setting (INTFLAGSASET) the flags. The individual flags can be set by writing a one to
their bit locations in INFLAGSASET, and cleared by writing a one to their bit locations in INT--
Bit
7
6
5
4
3
2
1
0
–
–
–
–
–
–
TRNIE
SETUPIE
INTCTRLB
Read/Write
R
R
R
R
R
R
R/W
R/W
Initial Value
0
0
0
0
0
0
0
0