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XMEGA A [MANUAL]
8077I–AVR–11/2012
17.3.10 COMPL – Compare register Low
The COMPH and COMPL register pair represent the 16-bit value, COMP. COMP is constantly compared with the
counter value (CNT). A compare match will set COMPIF in the INTFLAGS register. Reading and writing 16-bit values
Due to synchronization between the RTC clock and system clock domains, there is a latency of two RTC clock cycles
from updating the register until this has an effect. Application software needs to check that the SYNCBUSY flag in the
If the COMP value is higher than the PER value, no RTC compare match interrupt requests or events will ever be
generated.
Bit 7:0 – COMP[7:0]: Compare value low byte
These bits hold the LSB of the 16-bit RTC compare value.
17.3.11 COMPH – Compare Register High
Bit 7:0 – COMP[15:8]: Compare Value High byte
These bits hold the MSB of the 16-bit RTC compare value.
Bit
7
65
43
210
+0x0C
COMP[7:0]
Read/Write
R/W
Initial Value
0
00
000
Bit
7
65
43
210
+0x0D
COMP[15:8]
Read/Write
R/W
Initial Value
0
00
000