Day Alarm Register (Rdayar) - Hitachi SH7751 Hardware Manual

Bit: 7
ENB
Initial value: 0
R/W: R/W
Day-of-week code
Day of week

11.2.13 Day Alarm Register (RDAYAR)

RDAYAR is an 8-bit readable/writable register used as an alarm register for the RTC's BCD-
coded day value counter, RDAYCNT. When the ENB bit is set to 1, the RDAYAR value is
compared with the RDAYCNT value. Comparison between the counter and the alarm register is
performed for those registers among RSECAR, RMINAR, RHRAR, RWKAR, RDAYAR, and
RMONAR in which the ENB bit is set to 1, and the RCR1 alarm flag is set when the respective
values all match.
The setting range is decimal 01 to 31 + ENB bit. The RTC will not operate normally if any other
value is set. The setting range for RDAYAR depends on the month and whether the year is a leap
year, so care is required when making the setting.
The ENB bit in RDAYAR is initialized by a power-on reset. The other fields in RDAYAR are not
initialized by a power-on or manual reset, or in standby mode.
Bit 6 is always read as 0. A write to this bit is invalid, but the write value should always be 0.
Bit: 7
ENB
Initial value: 0
R/W: R/W
Rev. 3.0, 04/02, page 274 of 1064
6 5
— —
0 0
R R
0 1
Sun Mon
6 5
— 10-day units
0
Undefined Undefined Undefined Undefined Undefined Undefined
R R/W
4 3
— —
0 0
R R
2 3
Tue Wed
4 3
R/W R/W
2 1
Day-of-week code
Undefined Undefined Undefined
R/W R/W
4 5
Thu Fri
2 1
1-day units
R/W R/W
0
R/W
6
Sat
0
R/W