NS32FX211 Datasheet, PDF (5/12 Pages) National Semiconductor (TI) – Microprocessor Compatible Real Time C

Functional Description (Continued)
RCH only used for
recharageable batteries
FIGURE 3 Typical System Connection Diagram
TL F 11011 – 5
logic 1 The units and tens of seconds are set up by the
processor giving time setting to the nearest second All
three registers can be read by the processor for time output
Minutes Counters
There are two minutes counters
a units of minutes
b tens of minutes
Both registers may be read to or written from as required
Hours Counters
There are two hours counters
a units of hours
b tens of hours
Both counters may be accessed for read or write operations
as desired
In 12-hour mode the tens of hours register has only one
active bit and the top three bits are set to logic 0 Data bit 1
of the clock setting register is the AM PM indicator logic 0
indicating AM logic 1 for PM
When 24-hour mode is programmed the tens of hours reg-
ister reads out two bits of data and the two most significant
bits are set to logic 0 There is no AM PM indication and bit
1 of the clock setting register will read out a logic 0
In both 12 24-hour modes the units of hours will read out
four active data bits 12 or 24-hour mode is selected by bit 0
of the clock setting register logic 0 for 12-hour mode logic
1 for the 24-hour mode
Days Counters
There are two days counters
a units of day
b tens of days
The days counters will count up to 28 29 30 or 31 depend-
ing on the state of the months counters and the leap year
counter The microprocessor has full read write access to
these registers
Months Counters
There are two months counters
a units of months
b tens of months
Both these counters have full read write access
Years Counters
There are two years counters
a units of years
b tens of years
Both these counters have full read write access The years
will count up to 99 and roll over to 00
5