Seiko Epson S1C17153, Technical Manual

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8 Real-TiMe ClOCK (RTC)
8-2 Seiko epson Corporation
S1C17153 TeChniCal Manual
(Rev. 1.0)
Minute counter
This 7-bit binary counter counts from 0 to 59 minutes with 1 carried over from the second counter. This counter
is also used as a 3-bit (0 to 5) + 4-bit (0 to 9) BCD counter by setting BCDMD/RTC_CTL register to 1. The
counter data can be read/written using RTCMIN[6:0]/RTC_MS register. The counter is reset to 0 when it reach-
es 60 minutes and outputs a carry over of 1 to the hour counter.
RTCMIN[6:0]
Binary mode 0–59
RTCMIN[3:0]
BCD mode 0–9 (1-minute digit)
RTCMIN[6:4]
0–5 (10-minute digit)
2.2 Minute Counter Figure 8.
hour counter
This 6-bit binary counter counts from 0 to 23 o’clock (24-hour mode) or from 1 to 12 o’clock (12-hour mode)
with 1 carried over from the minute counter. This counter is also used as a 2-bit (0 to 2 or 0 to 1) + 4-bit (0
to 9) BCD counter by setting BCDMD/RTC_CTL register to 1. The counter data can be read/written using
RTCHOUR[5:0]/RTC_H register.
AMPM
0 (AM)/1 (PM)
0/1
AMPM
0/1
RTCHOUR[5:0]
24-hour mode
Binary mode 0–23
RTCHOUR[3:0]
BCD mode 0–9 (1-hour digit)
RTCHOUR[5:4]
0–2 (10-hour digit)
RTCHOUR[5:0]
12-hour mode
1–12
RTCHOUR[3:0]
0–9 (1-hour digit)
RTCHOUR[5:4]
0–1 (10-hour digit)
2.3 Hour Counter Figure 8.
2.1 Hour Counter Values Table 8.
Time
24-hour mode 12-hour mode
RTCHOUR[5:0]
(binary)
RTCHOUR[5:0]
(BCD)
RTCHOUR[5:0]
(binary)
RTCHOUR[5:0]
(BCD)
AMPM
0 o'clock (12am) 0x0 0x00 0xc 0x12 0
1 o'clock (1am) 0x1 0x01 0x1 0x01 0
2 o'clock (2am) 0x2 0x02 0x2 0x02 0
3 o'clock (3am) 0x3 0x03 0x3 0x03 0
4 o'clock (4am) 0x4 0x04 0x4 0x04 0
5 o'clock (5am) 0x5 0x05 0x5 0x05 0
6 o'clock (6am) 0x6 0x06 0x6 0x06 0
7 o'clock (7am) 0x7 0x07 0x7 0x07 0
8 o'clock (8am) 0x8 0x08 0x8 0x08 0
9 o'clock (9am) 0x9 0x09 0x9 0x09 0
10 o'clock (10am) 0xa 0x10 0xa 0x10 0
11 o'clock (11am) 0xb 0x11 0xb 0x11 0
12 o'clock (12pm) 0xc 0x12 0xc 0x12 1
13 o'clock (1pm) 0xd 0x13 0x1 0x01 1
14 o'clock (2pm) 0xe 0x14 0x2 0x02 1
15 o'clock (3pm) 0xf 0x15 0x3 0x03 1
16 o'clock (4pm) 0x10 0x16 0x4 0x04 1
17 o'clock (5pm) 0x11 0x17 0x5 0x05 1
18 o'clock (6pm) 0x12 0x18 0x6 0x06 1
19 o'clock (7pm) 0x13 0x19 0x7 0x07 1
20 o'clock (8pm) 0x14 0x20 0x8 0x08 1
21 o'clock (9pm) 0x15 0x21 0x9 0x09 1
22 o'clock (10pm) 0x16 0x22 0xa 0x10 1
23 o'clock (11pm) 0x17 0x23 0xb 0x11 1
initial counter values
An initial reset does not initialize the counter values. Be sure to initialize the counters via software.