9 REAL-TIME CLOCK (RTC)
9-8
Seiko Epson Corporation
S1C17651 TECHNICAL MANUAL
D7
INT1H: 1-Hour Interrupt Flag Bit
Indicates 1-hour interrupt cause occurrence status. INT1H is set to 1 at the same time the minute
counter changes from 59 to 0.
D6
INT10M: 10-Minute Interrupt Flag Bit
Indicates 10-minute interrupt cause occurrence status. INT10M is set to 1 at the same time the minute
counter changes from 9 to 10, 19 to 20, 29 to 30, 39 to 40, 49 to 50, or 59 to 0.
D5
INT1M: 1-Minute Interrupt Flag Bit
Indicates 1-minute interrupt cause occurrence status. INT1M is set to 1 at the same time the second
counter changes from 59 to 0.
D4
INT10S: 10-Second Interrupt Flag Bit
Indicates 10-second interrupt cause occurrence status. INT10S is set to 1 at the same time the second
counter changes from 9 to 10, 19 to 20, 29 to 30, 39 to 40, 49 to 50, or 59 to 0.
D3
INT1HZ: 1 Hz Interrupt Flag Bit
Indicates 1 Hz interrupt cause occurrence status. INT1HZ is set to 1 in the divider 1 Hz signal cycles.
D2
INT4HZ: 4 Hz Interrupt Flag Bit
Indicates 4 Hz interrupt cause occurrence status. INT4HZ is set to 1 in the divider 4 Hz signal cycles.
D1
INT8HZ: 8 Hz Interrupt Flag Bit
Indicates 8 Hz interrupt cause occurrence status. INT8HZ is set to 1 in the divider 8 Hz signal cycles.
D0
INT32HZ: 32 Hz Interrupt Flag Bit
Indicates 32 Hz interrupt cause occurrence status. INT32HZ is set to 1 in the divider 32 Hz signal
cycles.
RTC Minute/Second Counter Register (RTC_MS)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
RTC
Minute/Second
Counter
Register
(RTC_MS)
0x56c6
(16 bits)
D15
–
reserved
–
0 when being read.
D14–8 RTCMIN
[6:0]
Minute counter
0x0 to 0x3b (binary mode)
0x00 to 0x59 (BCD mode)
X
R/W
D7
–
reserved
–
0 when being read.
D6–0 RTCSEC
[6:0]
Second counter
0x0 to 0x3b (binary mode)
0x00 to 0x59 (BCD mode)
X
R/W
D15
Reserved
D[14:8]
RTCMIN[6:0]: Minute Counter Bits
These bits are used to read and write data from/to the minute counter. (Default: undefined)
The effective range of the read/setting values are as follows:
RTCMIN[6:0] = 0x0 to 0x3b (0 to 59 minutes) in binary mode (BCDMD = 0)
RTCMIN[6:4] = 0x0 to 0x5 (10-minute digit) and RTCMIN[3:0] = 0x0 to 0x9 (1-minute digit) in
BCD mode (BCDMD = 1)
D7
Reserved
D[6:0]
RTCSEC[6:0]: Second Counter Bits
These bits are used to read and write data from/to the second counter. (Default: undefined)
The effective range of the read/setting values are as follows:
RTCSEC[6:0] = 0x0 to 0x3b (0 to 59 seconds) in binary mode (BCDMD = 0)
RTCSEC[6:4] = 0x0 to 0x5 (10-second digit) and RTCSEC[3:0] = 0x0 to 0x9 (1-second digit) in
BCD mode (BCDMD = 1)
Notes: For the counter read and write procedures, see Section 9.3.5, “Counter Read,” and Section
9.3.4, “Counter Settings.”
Do not set the counters while the RTC is running, as proper settings to the counters cannot be
guaranteed.