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DS1307(4)		 BSD Kernel Interfaces Manual		     DS1307(4)

NAME
     ds1307 -- 64 x 8, serial, i2c real-time clock

SYNOPSIS
     device iic
     device iicbus
     device ds1307

DESCRIPTION
     The ds1307	serial real-time clock (RTC) is	a low-power, full binary-coded
     decimal (BCD) clock/calendar plus 56 bytes	of NV SRAM.

     The ds1307	has a built-in power-sense circuit that	detects	power failures
     and automatically switches	to the backup supply.  Timekeeping operation
     continues while the part operates from the	backup supply.

     Access to ds1307 settings is made with the	sysctl(8) interface:

     dev.ds1307.0.%desc: Maxim DS1307 RTC
     dev.ds1307.0.%driver: ds1307
     dev.ds1307.0.%location: addr=0xd0
     dev.ds1307.0.%pnpinfo: name=rtc compat=maxim,ds1307
     dev.ds1307.0.%parent: iicbus1
     dev.ds1307.0.sqwe:	1
     dev.ds1307.0.sqw_freq: 32768
     dev.ds1307.0.sqw_out: 0

     dev.ds1307.%d.sqwe	     If	set to 1, the SQW pin drives a square-wave of
			     dev.ds1307.%d.sqw_freq frequency.	If set to 0,
			     the output	level of SQW pin is controlled by
			     dev.ds1307.%d.sqw_out.

     dev.ds1307.%d.sqw_freq  Select the	frequency of the SQW pin when the
			     square-wave output	is enabled on
			     dev.ds1307.%d.sqwe.  It can be set	to 1, 4096,
			     8192 and 32768.

     dev.ds1307.%d.sqw_out   Set the output level of the SQW pin when
			     dev.ds1307.%d.sqwe	is set to 0.

     Please check the ds1307 datasheet for more	details.

     On	a device.hints(5) based	system,	such as	MIPS, these values are config-
     urable for	ds1307:

     hint.ds1307.%d.at	  The iicbus(4)	that the ds1307	is connected to.

     hint.ds1307.%d.addr  The i2c address of ds1307.

     On	a FDT(4) based system the following properties must be set:

     compatible	 Must always be	set to "dallas,ds1307" or "maxim,ds1307".

     reg	 The i2c address of ds1307.  The default address for ds1307 is
		 0xd0.

SEE ALSO
     fdt(4), iic(4), iicbus(4),	sysctl(8)

HISTORY
     The ds1307	driver first appeared in FreeBSD 11.0.

AUTHORS
     The ds1307	driver and this	manual page were written by Luiz Otavio	O
     Souza <loos@FreeBSD.org>.

BSD				 March 7, 2015				   BSD

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | HISTORY | AUTHORS

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