PXD10RM Datasheet, PDF (1088/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

Field
ROVREN
RTCVAL
APIEN
APIIE
CLKSEL
DIV512EN
DIV32EN
APIVAL
Table 31-2. RTCC field descriptions (continued)
Description
Counter Roll Over Interrupt Enable
The ROVREN bit enables interrupt requests when the RTC has rolled over from 0xffff_ffff to
0x0000_0000. The RTCIE bit must also be set in order to generate an interrupt from a counter
rollover.
1 RTC rollover interrupt enabled
0 RTC rollover interrupt disabled
RTC Compare Value
The RTCVAL bits are compared to bits 10:21 of the RTC counter and if match sets RTCF.
RTCVAL may only be updated when CNTEN is 0.
Note: RTCVAL should not be set to 0.
Autonomous Periodic Interrupt Enable
The APIEN bit enables the autonomous periodic interrupt function.
1 API enabled
0 API disabled
API Interrupt Enable
The APIIE bit enables interrupts requests to the system if APIF is asserted.
1 API interrupts enabled
0 API interrupts disabled
Clock Select
The CLKSEL[0:1] bits select the clock source for the RTC. CLKSEL may only be updated when
CNTEN is 0. The user should ensure that oscillator is enabled before selecting it as a clock
source for RTC.
00 32 KHz SXOSC
01 128 kHz SIRC
10 16 MHz FIRC
11 16 MHz FXOSC
Divide by 512 enable
The DIV512EN bit enables the 512 clock divider. DIV512EN may only be updated when CNTEN
is 0.
0 Divide by 512 is disabled.
1 Divide by 512 is enabled.
Divide by 32 enable
The DIV32EN bit enables the 32 clock divider. DIV32EN may only be updated when CNTEN is 0.
0 Divide by 32 is disabled.
1 Divide by 32 is enabled.
API Compare Value
The APIVAL bits are compared to an offset value based on bits 22:31 of the RTC counter and if
match asserts an interrupt/wakeup request. APIVAL may only be updated when APIEN is 0 or
API function is undefined.
Note: API functionality starts only when APIVAL is nonzero. The first API interrupt takes two
more cycles because of synchronization of APIVAL to the RTC clock. After that, interrupts
are periodic in nature. The minimum supported value of APIVAL is 4.
31-6
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor