It seems the ds1307 and ds1371 count and store time differently. Below is the descriptions. This must explain why I can not program the ds1371 on my tool.
The DS1371 is a real-time clock (RTC) with a I2C serial interface that provides elapsed seconds from a
user-defined starting point in a 32-bit counter (Figure 2). A 24-bit counter can be configured as either a
watchdog counter or as an alarm counter.
The time-of-day counter is a 32-bit up counter. The contents can be read or written by accessing the
address range 00h–03h. When the counter is read, the current time of day is latched into a register, which
is output on the serial data line while the counter continues to increment. Writing to the counter resets the
countdown chain for the time-of-day counter (Figure 2). The watchdog countdown chain is unaffected. If
the square-wave output is enabled and is set to 1Hz, the output resets when the countdown chain is reset.
Because the other square-wave frequencies are derived before the section of the countdown chain that is
reset, the other frequencies are unaffected by a write to the time-of-day counter.
The DS1307 is a low-power clock/calendar with 56 bytes of battery-backed SRAM. The clock/calendar provides
seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically
adjusted for months with fewer than 31 days, including corrections for leap year.The time and calendar information is obtained by reading the appropriate register bytes. Table 2 shows the RTC
registers. The time and calendar are set or initialized by writing the appropriate register bytes. The contents of the
time and calendar registers are in the BCD format. The day-of-week register increments at midnight. Values that
correspond to the day of week are user-defined but must be sequential (i.e., if 1 equals Sunday, then 2 equals
Monday, and so on.) Illogical time and date entries result in undefined operation. Bit 7 of Register 0 is the clock halt
(CH) bit. When this bit is set to 1, the oscillator is disabled. When cleared to 0, the oscillator is enabled. On first
application of power to the device the time and date registers are typically reset to 01/01/00 01 00:00:00
(MM/DD/YY DOW HH:MM:SS). The CH bit in the seconds register will be set to a 1. The clock can be halted
whenever the timekeeping functions are not required, which minimizes current (IBATDR).
The DS1307 can be run in either 12-hour or 24-hour mode. Bit 6 of the hours register is defined as the 12-hour or
24-hour mode-select bit. When high, the 12-hour mode is selected. In the 12-hour mode, bit 5 is the AM/PM bit with
logic high being PM. In the 24-hour mode, bit 5 is the second 10-hour bit (20 to 23 hours). The hours value must be
re-entered whenever the 12/24-hour mode bit is changed.
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