Ubuntu Manpage: DS2505, DS2505-UNW - Add-Only Memory (16 kBit), UniqueWare Add-Only Memory (16 kBit)

NAME

       DS2505, DS2505-UNW - Add-Only Memory (16 kBit), UniqueWare Add-Only Memory (16 kBit)

       DS1985, DS1985U
              - Add-Only iButton (16 kBit), UniqueWare iButton (16 kBit)

SYNOPSIS

       EPROM add-only memory.

       0B  [.]XXXXXXXXXXXX[XX][/[  memory  | pages/page.[0-63|ALL] | address | crc8 | id | locator | r_address |
       r_id | r_locator | type ]]

       8B [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-63|ALL] | address | crc8 | id | locator  |  r_address  |
       r_id | r_locator | type ]]

FAMILY CODE

       0B     DS2505 DS1985

       8B     DS2505-UNW DS1985U

SPECIAL PROPERTIES

   memory
       read-write, binary
       2048 bytes of memory. Initially all bits are set to 1. Writing zero permanently alters the memory.

   pages/page.0 ... pages/page.63 pages/page.ALL
       read-write, yes-no
       Memory  is split into 64 pages of 32 bytes each.  ALL is an aggregate of the pages. 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 applications 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 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 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-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 (humidity, 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 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 individually 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 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 communication. Still the fundemental goal has been ease of use,
flexibility and correctness rather than speed.

DS2505 DS1985
The DS2505 (3) is used for write-once incremental storage. It's main advantage is for audit trails (i.e.
a digital purse).

The DS2505-UNW is one of the UniqueWare class of devices. Some of the memory was preprogramed at the
factory. See the datasheet for specifics. The DS2502 , DS2505 , and DS2506 differ in their function by
the amount of on-board memory they possess. (The internal protocols are slightly different, but the OWFS
system handles this automatically.

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 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/DS2505.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS2502-UNW-DS2506S-UNW.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS1985-F3-DS1985-F5.pdf
       http://pdfserv.maxim-ic.com/en/ds/DS1982U-DS1986U.pdf

   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 (3) EDS0066 (3) EDS0068 (3)

   Moisture
       EEEF (3) DS2438 (3)

AVAILABILITY

       http://www.owfs.org

AUTHOR

       Paul Alfille (paul.alfille@gmail.com)