Table of Contents
Advertisement
8 Real-TiMe ClOCK (RTC)
D[7:4]
RTCYh[3:0]: RTC 10-year Counter Bits
These bits comprise a 4-bit BCD counter used to count tens of years. The counter counts from 0 to 9
with a carry over of 1 from the 1-year counter.
D[3:0]
RTCYl[3:0]: RTC 1-year Counter Bits
These bits comprise a 4-bit BCD counter used to count units of years.
The counter counts from 0 to 9 with a carry over of 1 from the month counter. This counter is reset to 0
after 9 and outputs a carry over of 1 to the 10-year counter.
RTC Days of Week Register (RTC_WeeK)
Register name address
Bit
RTC Days of
0x514a
D7–3 –
Week Register
(8 bits)
D2–0 RTCWK[2:0] RTC days of week counter
(RTC_WeeK)
* Software reset (RTCRST → 1 → 0) does not affect the counter values. This register retains the value set before a software reset is
performed.
notes: • Data should not be read from or written to the counters while 1 is being carried over. (See
Section 8.3.5, "Counter Hold and Busy Flag," and Section 8.3.7, "Counter Read.")
• Rewriting RTC24H/RTC_CNTL0 register may corrupt the count data in this register. Therefore,
after changing the RTC24H setting, be sure to set up this register again.
D[7:3]
Reserved
D[2:0]
RTCWK[2:0]: RTC Days of Week Counter Bits
This is a septenary counter (that counts from 0 to 6) representing days of the week. This counter counts
at the same timing as the 1-day counter.
The correspondence between the counter values and days of the week can be set in a program as de-
sired. Table 8.5.3 lists the basic correspondence.
Table 8.
8-16
name
Function
reserved
5.3 Correspondence between Counter Values and Days of the Week
RTCWK[2:0]
0x6
0x5
0x4
0x3
0x2
0x1
0x0
(Default: indeterminate, software reset: previous value retained)
Seiko epson Corporation
Setting
init. R/W
–
–
RTCWK[2:0]
Days of week X (*) R/W
0x7
–
0x6
Saturday
0x5
Friday
0x4
Thursday
0x3
Wednesday
0x2
Tuesday
0x1
Monday
0x0
Sunday
Days of the week
Saturday
Friday
Thursday
Wednesday
Tuesday
Monday
Sunday
S1C17624/604/622/602/621 TeChniCal Manual
Remarks
–
0 when being read.
Advertisement
Table of Contents
