RX8111CE
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23
ETM61E-01
14.1.2. Week Counter
The day (of the week) is indicated by 7 bits, bit 0 to bit 6.
The day data values are counted as: Day 01h
→
Day 02h
→
Day 04h
→
Day 08h
→
Day 10h
→
Day 20h
→
Day 40h
→
Day 01h
→
Day 02h, etc.
It is incremented when carry is generated from the HOUR register. This register does not generate carry to a higher register. Since
this register is not connected with the YEAR, MONTH and DAY registers, it needs to be set again with the matching day of the
week if any of the YEAR, MONTH or DAY registers have been changed.
When not use Week data, It is not necessary for Week register to be initialized.
Do not set "1" to more than one day at the same time.
Table 14 Setting example of the week register value
Day
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
Data
Sunday
0
0
0
0
0
0
0
1
01 h
Monday
0
0
0
0
0
0
1
0
02 h
Tuesday
0
0
0
0
0
1
0
0
04 h
Wednesday
0
0
0
0
1
0
0
0
08 h
Thursday
0
0
0
1
0
0
0
0
10 h
Friday
0
0
1
0
0
0
0
0
20 h
Saturday
0
1
0
0
0
0
0
0
40 h
14.1.3. Calendar Counter
1) [DAY],
[MONTH]
register
The DAY register is a variable (between 28-base and 31-base) BCD counter that is influenced by the month and the leap year. The
MONTH register is a 12-base BCD counter triggered by carry over of the day register.
Table 15 DAY, MONTH register
Jan.
Feb.
Mar
Apr.
May
June
July
Aug.
Sep.
Oct.
Nov.
Dec.
Days
Normal year
31
28
31
30
31
30
31
31
30
31
30
31
Leap year
29
2) [YEAR]
register
This register is a BCD counter for years 00 to 99.
The leap year is automatically determined and influences the DAY register.
This RTC processes following years as leap years: 00,04,08,12, 96.
User software correction is needed in the years 2100, 2200, 2300 as they are common years.
Definition of leap years
Leap year : year divisible by 4, year divisible by 400
Ex. 2000, 2004, 2008, 2012, 2096, 2400, 2800,
Common year: year indivisible by 4, year divisible by 100
Ex. 2001, 2002, 2003, 2005, 2099, 2100, 2200, 2300, 2500,,
