Epson S1C17624 Technical Manual page 85

D1 RTCiMD: RTC interrupt Mode Select Bit
This bit specifies whether RTC interrupts are to be generated by an edge or level of the interrupt request
signal.
1 (R/W): Level sensed (software reset value)
0 (R/W): Edge triggered
When an edge-triggered interrupt is selected and used to turn off SLEEP mode via the CLG, note that
no interrupts will be generated because the ITC is inactive. When an RTC interrupt handler routine must
be executed after exiting SLEEP mode, select a level-sensed interrupt.
D0 RTCien: RTC interrupt enable Bit
This bit enables or disables RTC interrupt request output to the ITC.
1 (R/W): Enable interrupts
0 (R/W): Disable interrupts (software reset value)
To generate an RTC interrupt or use an RTC interrupt request signal to turn off SLEEP mode, set this
bit to 1. When this bit is 0, no interrupts are generated and SLEEP mode cannot be turned off.
note: The value of RTCIEN is indeterminate after power-on, and not initialized to 0 by initial reset. To
prevent the occurrence of unwanted RTC interrupts, be sure to clear this bit in software after
power-on and initial reset.
RTC Control 0 Register (RTC_CnTl0)
Register name address Bit
RTC Control 0 0x5142 D7–5 –
Register (8 bits)
D4
(RTC_CnTl0)
D3
D2
D1
D0
Init.: ( ) indicates the value set after a software reset (RTCRST → 1 → 0) is performed.
D[7:5] Reserved
D4 RTC24h: 24h/12h Mode Select Bit
This bit selects whether to use the hour counter in 24-hour or 12-hour mode.
1 (R/W): 24-hour mode
0 (R/W): 12-hour mode (software reset value)
The count range of hour counters changes with this selection. Basically, this setting should be changed
while the counters are idle. Since this register is assigned a control bit (D1) to start the counters, 12-
hour or 24-hour mode may be selected when starting the counters.
note: Rewriting RTC24H may corrupt the count data for hours, days, months, years, or days of the
week. Therefore, after changing the RTC24H setting, be sure to set data back in these coun-
ters again.
D3 Reserved
D2 RTCaDJ: 30-second adjustment Bit
This bit executes 30-second correction.
1 (W): Execute 30-second correction
0 (W): Has no effect
1 (R): 30-second correction being executed
0 (R): 30-second correction completed (not being executed) (software reset value)
The description "30-second correction" means adding 1 to the minutes when seconds of the time clock
are in the 30-to-59 second range, and doing nothing in the 0-to-29 second range. This function may be
used to round up seconds to minutes when resetting seconds in an application.
S1C17624/604/622/602/621 TeChniCal Manual
name Function
reserved
RTC24h 24H/12H mode select
–
reserved
RTCaDJ
30-second adjustment
RTCSTP Divider run/stop control
RTCRST
Software reset
Seiko epson Corporation
8 Real-TiMe ClOCK (RTC)
Setting init. R/W
–
1 24H 0 12H X (0) R/W
–
1 Adjust 0 – X (0) R/W
1 Stop 0 Run X (0) R/W
1 Reset 0 – X (0) R/W
Remarks
– – 0 when being read.
– – 0 when being read.
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