Epson S1C31D50 Technical Manual

Also see for Buzzer S1C31D51: Manual Manual Getting started

10 REAL-TIME CLOCK (RTCA)10-10 Seiko Epson Corporation S1C31D50/D51 TECHNICAL MANUAL(Rev. 2.00)Bit 7 RTC1HZBit 6 RTC2HZBit 5 RTC4HZBit 4 RTC8HZBit 3 RTC16HZBit 2 RTC32HZBit 1 RTC64HZBit 0 RTC128HZ1 Hz counter data can be read from these bits.The following shows the correspondence between the bit and frequency:RTCASEC.RTC1HZ bit: 1 HzRTCASEC.RTC2HZ bit: 2 HzRTCASEC.RTC4HZ bit: 4 HzRTCASEC.RTC8HZ bit: 8 HzRTCASEC.RTC16HZ bit: 16 HzRTCASEC.RTC32HZ bit: 32 HzRTCASEC.RTC64HZ bit: 64 HzRTCASEC.RTC128HZ bit: 128 HzNote: The counter value may not be read correctly while the 1 Hz counter is running. These bitsmust be read twice and assume the counter value was read successfully if the two read re-sults are the same.RTCA Hour/Minute RegisterRegister name Bit Bit name Initial Reset R/W RemarksRTCAHUR 15 – 0 – R –14 RTCAP 0 H0 R/W13–12 RTCHH[1:0] 0x1 H0 R/W11–8 RTCHL[3:0] 0x2 H0 R/W7 – 0 – R6–4 RTCMIH[2:0] 0x0 H0 R/W3–0 RTCMIL[3:0] 0x0 H0 R/WBit 15 ReservedBit 14 RTCAPThis bit is used to set and read A.M. or P.M. data in 12H mode (RTCACTLL.RTC24H bit = 0).1 (R/W): P.M.0 (R/W): A.M.In 24H mode (RTCACTLL.RTC24H bit = 1), this bit is fixed at 0 and writing 1 is ignored. However,if the RTCAHUR.RTCAP bit = 1 when changed to 24H mode, it goes 0 at the next count-up timing ofthe hour counter.Bits 13–12 RTCHH[1:0]Bits 11–8 RTCHL[3:0]The RTCAHUR.RTCHH[1:0] bits and the RTCAHUR.RTCHL[3:0] bits are used to set and read the10-hour digit and the 1-hour digit of the hour counter, respectively. The setting/read values are a BCDcode within the range from 1 to 12 in 12H mode or 0 to 23 in 24H mode.Note: Be sure to avoid writing to the RTCAHUR.RTCHH[1:0]/RTCHL[3:0] bits while the RTCACTLL.RTCBSY bit = 1.Bit 7 Reserved