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[Explorare]

I try to use a HTU21D (3.3V) and a RS1307 (5V) at the same time on Arduino Pro Mini (5V). I connect the Arduino I2C wires to the 5V side on TXS0108E,so as RS1307, and connect HTU21D on the 3.3V side. But when I drive the OE on TXS0108E HIGH, the output of RS1307 became strange as below:

2165/165/165 (Saturday) 165:165:85
since midnight 1/1/1970 = 1552693585s = 17970d
now + 7d + 30s: 2019/3/23 12:16:31
24935

The Arduino can't detect RS1307. But if I connect the OE to GND, RS1307 worked again, but HTU21D will stop working, since it will make TXS0108E into High-Z state.

So how to make HTU21D and RS1307 works at the same time using TXS0108E?

Thanks

[Valen]

What is a RS1307? A real time clock chip I presume. But Google doesn't know about it. A DS1307 however. Is that it?

Without a schematic how you have everything connected, and the code with which you receive the I2C datastream little can be explained. As always, for I2C communication to work pull-up resistors need to be present between the data and clock lines and the supply voltage.

You need to be clearer on what those date and time values mean. I don't understand what you are calculating there:

What time and date did you set the timekeeper registers to previously? (you have to correct the time/date as the battery supply could have ran out since leaving the factory or last powerup)
Which values from the timekeeper registers are received in the I2C stream now?
How much time since setting the time in the registers has passed?