User manual

DIGITAL-LOGIC AG MSM800SEV/SEL/BEV/XEV/XEL Detailed Manual V1.7
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The following table provides a summary of how these areas may be further divided.
Beginning Ending Checksum Description
00h 0Fh No RTC and Checksum
10h 2Dh Yes System Configuration
2Eh 2Fh No Checksum Value of 10h - 2Dh
30h 33h No Standard CMOS
34h 3Fh No Standard CMOS - SystemSoft Reserved
40h 5Bh Yes Extended CMOS - Chipset Specific
5Ch 5Dh No Checksum Value of 40h - 5Bh
5Eh 6Eh No Extended CMOS - Chipset Specific
6Fh 7Dh Yes Extended CMOS - Power Management
7Eh 7Fh No Checksum Value of 6Fh - 7Dh
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
Continued...