188
8331B–AVR–03/12
Atmel AVR XMEGA AU
14.12.10 INTFLAGS – Interrupt Flag register
• Bit 7:4 – CCxIF: Compare or Capture Channel x Interrupt Flag
The compare or capture interrupt flag (CCxIF) is set on a compare match or on an input capture
event on the corresponding CC channel.
For all modes of operation except for capture, the CCxIF will be set when a compare match
occurs between the count register (CNT) and the corresponding compare register (CCx). The
CCxIF is automatically cleared when the corresponding interrupt vector is executed.
For input capture operation, the CCxIF will be set if the corresponding compare buffer contains
valid data (i.e., when CCxBV is set). The flag will be cleared when the CCx register is read. Exe-
cuting the interrupt vector in this mode of operation will not clear the flag.
The flag can also be cleared by writing a one to its bit location.
The CCxIF can be used for requesting a DMA transfer. A DMA read or write access of the corre-
sponding CCx or CCxBUF will then clear the CCxIF and release the request.
• 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 – ERRIF: Error Interrupt Flag
This flag is set on multiple occasions, depending on the mode of operation.
In the FRQ or PWM waveform generation mode of operation, ERRIF is set on a fault detect con-
dition from the fault protection feature in the AWeX extention. For timer/counters which do not
have the AWeX extention available, this flag is never set in FRQ or PWM waveform generation
mode.
For capture operation, ERRIF is set if a buffer overflow occurs on any of the CC channels.
For event controlled QDEC operation, ERRIF is set when an incorrect index signal is given.
This flag is automatically cleared when the corresponding interrupt vector is executed. The flag
can also be cleared by writing a one to this location.
• Bit 0 – OVFIF: Overflow/Underflow Interrupt Flag
This flag is set either on a TOP (overflow) or BOTTOM (underflow) condition, depending on the
WGMODE setting. OVFIF is automatically cleared when the corresponding interrupt vector is
executed. The flag can also be cleared by writing a one to its bit location.
OVFIF can also be used for requesting a DMA transfer. A DMA write access of CNT, PER, or
PERBUF will then clear the OVFIF bit.
14.12.11 TEMP – Temporary register for 16-bit Access
The TEMP register is used for single-cycle, 16-bit access to the 16-bit timer/counter registers by
the CPU. The DMA controller has a separate temporary storage register. There is one common
TEMP register for all the 16-bit Timer/counter registers.
Bit
7
6
5
4
3
2
1
0
CCDIF
CCCIF
CCBIF
CCAIF
–
–
ERRIF
OVFIF
INTFLAGS
Read/Write
R/W
R/W
R/W
R/W
R
R
R/W
R/W
Initial Value
0
0
0
0
0
0
0
0
