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DS2423(3)		      One-Wire File System		       DS2423(3)

NAME
     DS2423 - 4kbit 1-Wire RAM with Counter

SYNOPSIS
     RAM and counters.

     1D      [.]XXXXXXXXXXXX[XX][/[	counter.[A|B|ALL]     |     memory     |
     pages/page.[0-15|ALL] | pages/count.[0-15|ALL] | address | crc8 | id |  lo-
     cator | r_address | r_id | r_locator | type ]]

FAMILY CODE
     1D

SPECIAL PROPERTIES
   counter.A counter.B counter.ALL
     read-only, unsigned integer
     Debounced	external  counter. Associated with RAM page.14 and page.15 Note:
     counter increments only. It is reset when the chip loses power.
     ALL returns the two values, separated by a comma.	They  are  read  sequen-
     tially.

     The  property  was  called counters prior to OWFS version 2.9p1 and the old
     name is invisibly recognized for backwards compatibility.

   memory
     read-write, binary
     512 bytes of memory.

   pages/page.0 ... pages/page.15 pages/page.ALL
     read-write, binary
     Memory is split into 16 pages of 32 bytes each. Memory is RAM, contents are
     lost when power is lost.  ALL is an aggregate of the pages.  Each	page  is
     accessed sequentially.

   pages/count.0 ... pages/count.15 pages/count.ALL
     read-only, unsigned integer

     Write access to each page of memory. Actually only page.12 and page.13 have
     write counters.
     page14  and page.15 's counters are associated with the external counters.A
     and counters.B triggers.
     The value 0xFFFFFFFF is returned for pages/count.0 through pages/count.11
     ALL is an aggregate of the counters, comma separated. Each page is accessed
     sequentially.

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

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

   family
     read-only, ascii
     The  8-bit  family code. Unique to each type of device. Given as upper case
     hexadecimal 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 hexadecimal digits (0-9A-F).
     r	id is the id in reverse order, which is often used in other applications
     and labeling.

   locator
   r_locator
     read-only, ascii
     Uses an extension of the 1-wire design from iButtonLink company that  asso-
     ciated  1-wire  physical connections with a unique 1-wire code. If the con-
     nection is behind a Link Locator the locator will show a unique 8-byte num-
     ber (16 character hexadecimal) 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.

DESCRIPTION
   1-Wire
     1-wire is a wiring protocol and series of devices designed and manufactured
     by Dallas Semiconductor, Inc. The bus is a low-power low-speed  low-connec-
     tor 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 (humidity, temper-
     ature, 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 encryption 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 indi-
     vidually discovered and addressed using their unique ID.

     Bus masters come in a variety of configurations including serial, parallel,
     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 principle is to create a virtual
     filesystem, with the unique ID being  the	directory,  and  the  individual
     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  con-
     sistent  interface. The goal is to provide an easy set of tools for a soft-
     ware 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  communication.
     Still  the  fundamental goal has been ease of use, flexibility and correct-
     ness rather than speed.

   DS2423
     The DS2423 (3) is used for its counters. The internal counters  (associated
     with pages 12 and 13) can detect memory tampering.

     The  external  counters A and B page been used in circuit design, such as a
     wind anometer.  OWFS system handles this automatically.

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

     Family Code
	    8 bits

     Address
	    48 bits

     CRC    8 bits

     Addressing under OWFS is in hexadecimal, 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/DS2423.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)  Infer-
     noEmbedded (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 (3) EDS0066 (3) EDS0068 (3)

   Moisture
     EEEF (3) DS2438 (3)

AVAILABILITY
     http://www.owfs.org

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

OWFS Manpage			      2003			       DS2423(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=DS2423&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

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