IN1307
RECOMMENDED LAYOUT FOR CRYSTAL
HOURS AND CALENDAR
Information on the time and date is obtained by means of reading the appropriate register
bytes. Hour registers of the real time are indicated in the Figure. Pre-setting and time and calendar
initialization are performed by means of writing the appropriate bytes. Information, contained in the
time and calendar registers, represents the binary-decimal code. Bit 7 of register 0 represents the
hour stop bit (CH). When this bit is set to “1” , the generator is off.
When switching on the power supply, the initial status of all registers is not determined. It is
necessary to enable the generator (bit CH = 0) when setting the initial configurations.
IN1307 operates in the 12-hour or in the 24-hour format. The bit 6 of the watch register de-
termines the operational mode. 12-hour mode corresponds to the high level. In the 12-hour mode
the bit 5 is the AM/PM bit. The high level corresponds to PM. In the 24-hour mode, the 5 is the
second bit of tens of hours (20 -23 hours).
During application of the signal “START” to the two-wire bus there happens transfer of the
real time to the auxiliary set of registers. The time data are read from these auxiliary registers,
while the watch proceeds in operation. This eliminates the necessity of repeated reading in case of
updating the basic registers in the access process.
REGISTERS RTC IN1307
2013, December, Ver.04
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IKSEMICON [ IK SEMICON CO., LTD ]
