Emerson 752I User Manual
Real-Time Clock:
Clock Operation
7-3
ST:
Stop bit
1=Stops the oscillator
0=Restarts the oscillator within one second
1=Stops the oscillator
0=Restarts the oscillator within one second
CEB:
Century Enable Bit
1=Causes CB to toggle either from 0 to 1 or from 1 to 0 at the turn of the century
0=CB will not toggle
1=Causes CB to toggle either from 0 to 1 or from 1 to 0 at the turn of the century
0=CB will not toggle
CB:
Century Bit
Day:
Day of the week
Date:
Day of the month
OUT:
Output level
1=Default at initial power-up
0=FT/OUT (pin 7) driven low when FT is also zero
1=Default at initial power-up
0=FT/OUT (pin 7) driven low when FT is also zero
FT:
Frequency Test bit
1=When oscillator is running at 32,768 Hz, the FT/OUT pin will toggle at 512 Hz
0=The FT/OUT pin is an output driver (default at initial power-up)
1=When oscillator is running at 32,768 Hz, the FT/OUT pin will toggle at 512 Hz
0=The FT/OUT pin is an output driver (default at initial power-up)
S:
Sign bit
1=Positive calibration
0=Negative calibration
1=Positive calibration
0=Negative calibration
Calibration:
Calibration bits
The calibration circuit adds or subtracts counts from the oscillator divider circuit at the
divide by 256 stage. The number of times pulses are blanked (subtracted, negative calibra-
tion) or split (added, positive calibration) depends on this five-bit byte. Adding counts
accelerates the clock, and subtracting counts slows the clock down.
The calibration circuit adds or subtracts counts from the oscillator divider circuit at the
divide by 256 stage. The number of times pulses are blanked (subtracted, negative calibra-
tion) or split (added, positive calibration) depends on this five-bit byte. Adding counts
accelerates the clock, and subtracting counts slows the clock down.
X:
Don’t care bit.