MSB900/L Detailed Technical Manual V1.0 |
CMOS Map
Location | Description | ||
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00h | Time of day (seconds) specified in BCD | ||
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01h | Alarm (seconds) specified in BCD | ||
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02h | Time of day (minutes) specified in BCD | ||
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03h | Alarm (minutes) specified in BCD | ||
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04h | Time of day (hours) specified in BCD | ||
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05h | Alarm (hours) specified in BCD | ||
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06h | Day of week specified in BCD | ||
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07h | Day of month specified in BCD | ||
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08h | Month specified in BCD | ||
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09h | Year specified in BCD | ||
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0Ah | Status Register A | ||
| Bit 7 | = | Update in progress |
| Bits | = | Time based frequency divider |
| Bits | = | Rate selection bits that define the periodic |
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| interrupt rate and output frequency. |
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0Bh | Status Register B | ||
| Bit 7 | = | Run/Halt |
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| 0 | Run |
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| 1 | Halt |
| Bit 6 | = | Periodic Timer |
|
| 0 | Disable |
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| 1 | Enable |
| Bit 5 | = | Alarm Interrupt |
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| 0 | Disable |
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| 1 | Enable |
| Bit 4 | = | Update Ended Interrupt |
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| 0 | Disable |
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| 1 | Enable |
| Bit 3 | = | Square Wave Interrupt |
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| 0 | Disable |
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| 1 | Enable |
| Bit 2 | = | Calendar Format |
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| 0 | BCD |
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| 1 | Binary |
| Bit 1 | = | Time Format |
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| 0 | |
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| 1 | |
| Bit 0 | = | Daylight Savings Time |
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| 0 | Disable |
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| 1 | Enable |
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0Ch | Status Register C | ||
| Bit 7 | = | Interrupt Flag |
| Bit 6 | = | Periodic Interrupt Flag |
| Bit 5 | = | Alarm Interrupt Flag |
| Bit 4 | = | Update Interrupt Flag |
| Bits | = | Reserved |
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0Dh | Status Register D | ||
| Bit 7 | = | Real Time Clock |
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| 0 | Lost Power |
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| 1 | Power |
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Continued...
30
