Kontron MSM800BEV - Manual (Page 47)

MSM800BEV / Detailed System Description
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6.11.1 CMOS Map
Location Description
00h Time of day (seconds) specified in BCD
01h Alarm (seconds) specified in BCD
02h Time of day (minutes) specified in BCD
03h Alarm (minutes) specified in BCD
04h Time of day (hours) specified in BCD
05h Alarm (hours) specified in BCD
06h Day of week specified in BCD
07h Day of month specified in BCD
08h Month specified in BCD
09h Year specified in BCD
0Ah
Status Register A
Bit 7
= Update in progress
Bits 6-4 = Time based frequency divider
Bits 3-0 = Rate selection bits that define the periodic interrupt rate and output frequency.
0Bh
Status Register B
Bit 7
= Run/Halt
0 = Run
1 = Halt
Bit 6 = Periodic Timer
0 = Disable
1 = Enable
Bit 5 = Alarm Interrupt
0 = Disable
1 = Enable
Bit 4 = Update Ended Interrupt
0 = Disable
1 = Enable
Bit 3 = Square Wave Interrupt
0 = Disable
1 = Enable
Bit 2 = Calendar Format
0 = BCD
1 = Binary
Bit 1 = Time Format
0 = 12-Hour
1 = 24-Hour
Bit 0 = Daylight Savings Time
0 = Disable
1 = Enable
0Ch
Status Register C
Bit 7
= Interrupt Flag
Bit 6 = Periodic Interrupt Flag
Bit 5 = Alarm Interrupt Flag
Bit 4 = Update Interrupt Flag
Bits 3-0 = Reserved
0Dh
Status Register D
Bit 7
= Real Time Clock
0 = Lost Power
1 = Power
0Eh
CMOS Location for Bad CMOS and Checksum Flags
Bit 7
= Flag for CMOS Lost Power
0 = Power OK
1 = Lost Power
Bit 6 = Flag for CMOS checksum bad
0 = Checksum is valid
1 = Checksum is bad
0Fh Shutdown Code