Renesas rl78 User Manual
RL78/G1A
CHAPTER 7 REAL-TIME CLOCK
7.3.13 Alarm minute register (ALARMWM)
This register is used to set minutes of alarm.
The ALARMWM register can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to 00H.
Caution Set a decimal value of 00 to 59 to this register in BCD code. If a value outside the range is set, the
alarm is not detected.
Figure 7-14. Format of Alarm Minute Register (ALARMWM)
Address: FFF9AH After reset: 00H R/W
Symbol
7 6 5 4 3 2 1 0
ALARMWM 0
WM40 WM20 WM10 WM8 WM4 WM2 WM1
7.3.14 Alarm hour register (ALARMWH)
This register is used to set hours of alarm.
The ALARMWH register can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to 12H.
However, the value of this register is 00H if the AMPM bit is set to 1 after reset.
Caution Set a decimal value of 00 to 23, 01 to 12, or 21 to 32 to this register in BCD code. If a value outside
the range is set, the alarm is not detected.
Figure 7-15. Format of Alarm Hour Register (ALARMWH)
Address: FFF9BH After reset: 12H R/W
Symbol
7 6 5 4 3 2 1 0
ALARMWH 0
0
WH20 WH10 WH8 WH4 WH2 WH1
Caution Bit 5 (WH20) of the ALARMWH register indicates AM(0)/PM(1) if AMPM = 0 (if the 12-hour system
is selected).
7.3.15 Alarm week register (ALARMWW)
This register is used to set date of alarm.
The ALARMWW register can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to 00H.
Figure 7-16. Format of Alarm Week Register (ALARMWW)
Address: FFF9CH After reset: 00H R/W
Symbol
7 6 5 4 3 2 1 0
ALARMWW 0
WW6 WW5 WW4 WW3 WW2 WW1 WW0
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Jul 04, 2013