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Joined: Mon May 27, 2013 1:13 am
Location: Tonight it's -28C
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I2C RTC DS1337 1Hz clock on SQW/INTB RS1 RS2 EOSC

Mon Jan 15, 2018 6:58 pm

I would like to have the DS1337 SQW/INTB (7) output ticking at 1Hz. Mine presently runs with a 35 us period i.e. 28 KHz or the RS1/2=1 setting but with the wrong crystal!

Is there any way of telling hwclock.sh, hwclock or rtc-ds1307 that .type=ds1337?

Is there then anyway of setting the Control Register bits INTCN, RS2 & RS1?

I originally used Gordon's WiringPi drivers for this so maybe I could use again before hwclock takes over the I2C!

For interest I am using a 0.2F capacitor in-place of battery backup and tentatively it looks like it might supply power for up to 3 days. Apart from the Ice-storm this would cover our typical outages.

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