Rtc Hour/Minute Alarm Register; Rtc Stopwatch Control Register - Epson S1C17M20 Technical Manual

9 REAL-TIME CLOCK (RTCA)
RTCALM1.RTCSHA[2:0] bits
0x0
0x0
· · ·
0x0
0x1
· · ·
0x5
Bits 7–0 Reserved

RTC Hour/Minute Alarm Register

Register name Bit
RTCALM2 15
14
13–12 RTCHHA[1:0]
11–8 RTCHLA[3:0]
7
6–4 RTCMIHA[2:0]
3–0 RTCMILA[3:0]
Bit 15 Reserved
Bit 14 RTCAPA
This bit sets A.M. or P.M. of the alarm time in 12H mode (RTCCTL.RTC24H bit = 0).
1 (R/W): P.M.
0 (R/W): A.M.
This setting is ineffective in 24H mode (RTCCTL.RTC24H bit = 1).
Bits 13–12 RTCHHA[1:0]
Bits 11–8 RTCHLA[3:0]
The RTCALM2.RTCHHA[1:0] bits and the RTCALM2.RTCHLA[3:0] bits set the 10-hour digit and
1-hour digit of the alarm time, respectively. A value within 1 to 12 o'clock in 12H mode or 0 to 23 in
24H mode can be set in BCD code.
Bit 7 Reserved
Bits 6–4 RTCMIHA[2:0]
Bits 3–0 RTCMILA[3:0]
The RTCALM2.RTCMIHA[2:0] bits and the RTCALM2.RTCMILA[3:0] bits set the 10-minute digit
and 1-minute digit of the alarm time, respectively. A value within 0 to 59 minutes can be set in BCD
code.

RTC Stopwatch Control Register

Register name Bit
RTCSWCTL 15–12 BCD10[3:0]
11–8 BCD100[3:0]
7–5 –
4
3–1 –
0
Bits 15–12 BCD10[3:0]
Bits 11–8 BCD100[3:0]
The 1/10-second and 1/100-second digits of the stopwatch counter can be read as a BCD code from
the RTCSWCTL.BCD10[3:0] bits and the RTCSWCTL.BCD100[3:0] bits, respectively.
9-8
Table 9.6.1 Setting Examples in BCD Code
Setting value in BCD code
RTCALM1.RTCSLA[3:0] bits
Bit name Initial
– 0
RTCAPA 0
0x0
0x0
– 0
0x0
0x0
Bit name Initial
0x0
0x0
0x0
SWRST 0
0x0
SWRUN 0
Seiko Epson Corporation
Alarm (second) setting
0x0
0x1
· · ·
0x9
0x0
· · ·
0x9
Reset R/W
– R –
H0 R/W
H0 R/W
H0 R/W
– R
H0 R/W
H0 R/W
Reset R/W
H0 R –
H0 R
– R
H0 W Read as 0.
– R –
H0 R/W
00 seconds
01 second
· · ·
09 seconds
10 seconds
· · ·
59 seconds
Remarks
Remarks
S1C17M20/M21/M22/M23/M24/M25
TECHNICAL MANUAL (Rev. 1.0)