Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
DS2404(3)		     One-Wire File System		     DS2404(3)

NAME
       DS2404 -	EconoRAM time chip

       DS2404S
	      -	Dual port memory plus time

       DS1994 -	4k plus	time iButton

       DS1427 -	Time iButton

SYNOPSIS
       Real time clock,	4kbit memory. 3-wire interface,	too.

       04.XXXXXXXXXXXX / alarm | auto |	cycle |	date | delay | interval	| mem-
       ory | pages/page.[0-15|ALL] | readonly/[memory|clock|cycle|interval]  |
       memory |	pages/page.[0-15|ALL] |	readonly/[memory|clock|cycle|interval]
       | running | set_alarm | start | trigger/[cycle,date,interval,udate,uin-
       terval] | udate | uinterval | address | crc8 | id | locator | r_address
       | r_id |	r_locator | type

       84.XXXXXXXXXXXX / alarm | auto |	cycle |	date | delay | interval	| mem-
       ory  | pages/page.[0-15|ALL] | readonly/[memory|clock|cycle|interval] |
       running | set_alarm | start  |  trigger/[cycle,date,interval,udate,uin-
       terval] | udate | uinterval | address | crc8 | id | present | type

FAMILY CODE
       04     DS2404 DS1994

       84     DS1427 DS2404S

SPECIAL	PROPERTIES
   alarm
       read-write, unsigned integer (0-111)
       Alarm  state  of	 the  DS2404  (3) triggered by time or counter events.
       Reading the alarm state clears the alarm.
       The alarm value is of the form CIR, where:

       C      cycle counter alarm
	      0	no
	      1	yes

       I      interval timer alarm
	      0	no
	      1	yes

       R      real-time	clock alarm
	      0	no
	      1	yes

   auto
       read-write, yes-no
       Flag for	mode of	interval counter operation. 0=manual 1=auto
       See the datasheet for details.

   date
       read-write, ascii
       26 character date representation	of the udate  value.  Increments  once
       per second while	running
       Actual internal representation has higher precision.
       Cannot be altered if readonly/clock is set.
       Setting date to a null string will put the current system time.
       Accepted	date formats are:
	 Sat[urday] March 12 12:23:59 2001
	 Apr[il] 4 9:34:56 2002
	 3/23/04 23:34:57
	 current locale	setting	(your system's format)

   delay
       read-write, yes-no
       Flag for	adding a delay to cycle	counter. 0=short 1-long
       See the datasheet under "IDEL" for details.

   interval
       read-write, date
       Interval	timer value, represented as a date string. More	typically will
       be used as uinterval to read the	actual elapsed seconds.

   memory
       read-write, binary
       512 bytes of memory. The	readonly/memory	flag prevents further change.

   pages/page.0	... pages/page.15 pages/page.ALL
       read-write, yes-no
       Memory is split into 16 pages of	32  bytes  each.  The  readonly/memory
       flag  prevents  further change.	ALL is an aggregate of the pages. Each
       page is accessed	sequentially.

   readonly/[memory|clock|interval|cycle]
       read-write, yes-no
       Permanently protect part	of the chip's function from alteration.

       readonly/memory
	      page.X and memory

       readonly/clock
	      date and udate

       readonly/interval
	      interval

       readonly/cycle
	      cycle

   running
       read-write, yes-no
       State of	the clock. 0=off 1=running.

   set_alarm
       read-write, unsigned integer (0-111)
       Which of	the alarm triggers are enabled in the DS2404 (3)
       The set_alarm value is of the form CIR, where:

       C      cycle counter alarm
	      0	no
	      1	yes

       I      interval timer alarm
	      0	no
	      1	yes

       R      real-time	clock alarm
	      0	no
	      1	yes

   start
       read-write, yes-no
       Flag for	starting the interval counter operation	if not in  auto	 mode.
       0=stop 1=start
       See the datasheet for details.

   trigger/[cycle,date,interval,udate,uinterval]
       read-write,varies
       Target value that will trigger the alarm	if the corresponding set_alarm
       field is	set.
       The format is the same as the similarly named  field  (i.e.   date  for
       trigger/date )

   udate
       read-write, unsigned integer
       Time  represented as a number.  udate increments	once per second, while
       running is on.
       Usually set to unix time	standard: number of seconds since Jan 1, 1970.
       The date	field will be the unix representation of udate and setting ei-
       ther will change	the other.

   uinterval
       read-write, unsigned interval
       Similar to the udate field, except corresponds to the interval value.

STANDARD PROPERTIES
   address
   r_address
       read-only, ascii
       The entire 64-bit unique	ID. Given as  upper  case  hexidecimal	digits
       (0-9A-F).
       address starts with the family code
       r address is the	address	in reverse order, which	is often used in other
       applications and	labeling.

   crc8
       read-only, ascii
       The 8-bit error correction portion. Uses	cyclic redundancy check.  Com-
       puted  from the preceding 56 bits of the	unique ID number. Given	as up-
       per case	hexidecimal digits (0-9A-F).

   family
       read-only, ascii
       The 8-bit family	code. Unique to	each type of device.  Given  as	 upper
       case hexidecimal	digits (0-9A-F).

   id
   r_id
       read-only, ascii
       The 48-bit middle portion of the	unique ID number. Does not include the
       family code or CRC. Given as upper case hexidecimal digits (0-9A-F).
       r id is the id in reverse order,	which is often used in other  applica-
       tions and labeling.

   locator
   r_locator
       read-only, ascii
       Uses  an	 extension  of the 1-wire design from iButtonLink company that
       associated 1-wire physical connections with a unique  1-wire  code.  If
       the  connection is behind a Link	Locator	the locator will show a	unique
       8-byte number (16 character hexidecimal)	starting with family code FE.
       If no Link Locator is between the device	and the	 master,  the  locator
       field will be all FF.
       r locator is the	locator	in reverse order.

   present (DEPRECATED)
       read-only, yes-no
       Is the device currently present on the 1-wire bus?

   type
       read-only, ascii
       Part  name  assigned by Dallas Semi. E.g.  DS2401 Alternative packaging
       (iButton	vs chip) will not be distiguished.

ALARMS
       None implemented.

DESCRIPTION
   1-Wire
       1-wire is a wiring protocol and series of devices designed and manufac-
       tured  by  Dallas  Semiconductor, Inc. The bus is a low-power low-speed
       low-connector scheme where the data line	can also provide power.

       Each device is uniquely and unalterably	numbered  during  manufacture.
       There  are a wide variety of devices, including memory, sensors (humid-
       ity, temperature, voltage, contact, current), switches, timers and data
       loggers.	 More complex devices (like thermocouple sensors) can be built
       with these basic	devices. There are also	1-wire devices that  have  en-
       cryption	included.

       The  1-wire  scheme uses	a single bus master and	multiple slaves	on the
       same wire. The bus master initiates all communication. The  slaves  can
       be individually discovered and addressed	using their unique ID.

       Bus  masters come in a variety of configurations	including serial, par-
       allel, i2c, network or USB adapters.

   OWFS	design
       OWFS is a suite of programs that	designed to make the  1-wire  bus  and
       its  devices  easily accessible.	The underlying priciple	is to create a
       virtual filesystem, with	the unique ID being the	directory, and the in-
       dividual	 properties of the device are represented as simple files that
       can be read and written.

       Details of the individual slave or master design	are  hidden  behind  a
       consistent interface. The goal is to provide an easy set	of tools for a
       software	designer to create monitoring or control  applications.	 There
       are some	performance enhancements in the	implementation,	including data
       caching,	parallel access	to bus masters,	and aggregation	of device com-
       munication.  Still the fundemental goal has been	ease of	use, flexibil-
       ity and correctness rather than speed.

   DS1427 DS1994 DS2404	DS2404S
       The DS1427 (3), DS1994 (3), DS2404  (3),	 and  DS2404S  (3)  family  of
       1-wire  devices includes	clock functions, with timers, memory, counters
       and alarms. It is possible to write-protect regians of memory. Uses in-
       clude software or hardware timing and control.

   Chips
       Both  the DS2404	(3) and	DS2404S	(3) have 1-wire	and 3-wire interfaces,
       which might be useful for transferring data between the 2  buses.  They
       act  as	a passive slave	to both	busses.	The DS2404 (3) and DS2404S (3)
       require an external source of power and an external crystal. They  also
       offer a reset and 1HZ clock pin.

   iButtons
       Both the	DS1427 and DS1994 offer	the memory, alarms, and	clock function
       in iButton format. Because the iButton is a  complete  sealed  package,
       battery	and  crystal are internal. Everything is access	via the	1-wire
       interface.

ADDRESSING
       All 1-wire devices are factory assigned a unique	64-bit	address.  This
       address is of the form:

       Family Code
	      8	bits

       Address
	      48 bits

       CRC    8	bits

       Addressing under	OWFS is	in hexidecimal,	of form:

	      01.123456789ABC

       where 01	is an example 8-bit family code, and 12345678ABC is an example
       48 bit address.

       The dot is optional, and	the CRC	code can  included.  If	 included,  it
       must be correct.

DATASHEET
       http://pdfserv.maxim-ic.com/en/ds/DS2404.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS2404S-C01.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS1994.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS1427.pdf

SEE ALSO
   Programs
       owfs  (1)  owhttpd  (1)	owftpd	(1)  owserver (1) owdir	(1) owread (1)
       owwrite (1) owpresent (1) owtap (1)

   Configuration and testing
       owfs (5)	owtap (1) owmon	(1)

   Language bindings
       owtcl (3) owperl	(3) owcapi (3)

   Clocks
       DS1427 (3) DS1904(3) DS1994 (3)	DS2404	(3)  DS2404S  (3)  DS2415  (3)
       DS2417 (3)

   ID
       DS2401 (3) DS2411 (3) DS1990A (3)

   Memory
       DS1982  (3)  DS1985  (3)	 DS1986	 (3)  DS1991 (3) DS1992	(3) DS1993 (3)
       DS1995 (3) DS1996 (3) DS2430A (3) DS2431	 (3)  DS2433  (3)  DS2502  (3)
       DS2506 (3) DS28E04 (3) DS28EC20 (3)

   Switches
       DS2405 (3) DS2406 (3) DS2408 (3)	DS2409 (3) DS2413 (3) DS28EA00 (3)

   Temperature
       DS1822  (3)  DS1825  (3)	 DS1820	(3) DS18B20 (3)	DS18S20	(3) DS1920 (3)
       DS1921 (3) DS1821 (3) DS28EA00 (3) DS28E04 (3) EDS0064 (3) EDS0065  (3)
       EDS0066	(3)  EDS0067  (3) EDS0068 (3) EDS0071 (3) EDS0072 (3) MAX31826
       (3)

   Humidity
       DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)

   Voltage
       DS2450 (3)

   Resistance
       DS2890 (3)

   Multifunction (current, voltage, temperature)
       DS2436 (3) DS2437 (3) DS2438 (3)	 DS2751	 (3)  DS2755  (3)  DS2756  (3)
       DS2760 (3) DS2770 (3) DS2780 (3)	DS2781 (3) DS2788 (3) DS2784 (3)

   Counter
       DS2423 (3)

   LCD Screen
       LCD (3) DS2408 (3)

   Crypto
       DS1977 (3)

   Pressure
       DS2406 (3) TAI8570 EDS0066 (3) EDS0068 (3)

   Moisture
       EEEF (3)	DS2438 (3)

AVAILABILITY
       http://www.owfs.org

AUTHOR
       Paul Alfille (paul.alfille@gmail.com)

OWFS Manpage			     2006			     DS2404(3)

NAME | SYNOPSIS | FAMILY CODE | SPECIAL PROPERTIES | STANDARD PROPERTIES | ALARMS | DESCRIPTION | ADDRESSING | DATASHEET | SEE ALSO | AVAILABILITY | AUTHOR

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=DS2404&sektion=3&manpath=FreeBSD+12.1-RELEASE+and+Ports>

home | help