1DS1995(3) One-Wire File System DS1995(3)
2
6 DS1995 - 16kbit Memory iButton
7
9 Non-volatile memory.
10 0A [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-63|ALL] | address |
12 crc8 | id | locator | r_address | r_id | r_locator | type ]]
13
15 0A DS1996
16
18 memory
19 read-write, binary
20 2048 bytes of memory.
21 pages/page.0 ... pages/page.63 pages/page.ALL
23 read-write, binary
24 Memory is split into 64 pages of 32 bytes each. ALL is an aggregate of
25 the pages. Each page is accessed sequentially.
26
28 address
29 r_address
30 read-only, ascii
31 The entire 64-bit unique ID. Given as upper case hexidecimal digits
32 (0-9A-F).
33 address starts with the family code
34 r address is the address in reverse order, which is often used in other
35 applications and labeling.
36 crc8
38 read-only, ascii
39 The 8-bit error correction portion. Uses cyclic redundancy check. Com‐
40 puted from the preceding 56 bits of the unique ID number. Given as
41 upper case hexidecimal digits (0-9A-F).
42 family
44 read-only, ascii
45 The 8-bit family code. Unique to each type of device. Given as upper
46 case hexidecimal digits (0-9A-F).
47 id
49 r_id
50 read-only, ascii
51 The 48-bit middle portion of the unique ID number. Does not include the
52 family code or CRC. Given as upper case hexidecimal digits (0-9A-F).
53 r id is the id in reverse order, which is often used in other applica‐
54 tions and labeling.
55 locator
57 r_locator
58 read-only, ascii
59 Uses an extension of the 1-wire design from iButtonLink company that
60 associated 1-wire physical connections with a unique 1-wire code. If
61 the connection is behind a Link Locator the locator will show a unique
62 8-byte number (16 character hexidecimal) starting with family code FE.
63 If no Link Locator is between the device and the master, the locator
64 field will be all FF.
65 r locator is the locator in reverse order.
66 present (DEPRECATED)
68 read-only, yes-no
69 Is the device currently present on the 1-wire bus?
70 type
72 read-only, ascii
73 Part name assigned by Dallas Semi. E.g. DS2401 Alternative packaging
74 (iButton vs chip) will not be distiguished.
75
77 None.
78
80 1-Wire
81 1-wire is a wiring protocol and series of devices designed and manufac‐
82 tured by Dallas Semiconductor, Inc. The bus is a low-power low-speed
83 low-connector scheme where the data line can also provide power.
84 Each device is uniquely and unalterably numbered during manufacture.
86 There are a wide variety of devices, including memory, sensors (humid‐
87 ity, temperature, voltage, contact, current), switches, timers and data
88 loggers. More complex devices (like thermocouple sensors) can be built
89 with these basic devices. There are also 1-wire devices that have
90 encryption included.
91 The 1-wire scheme uses a single bus master and multiple slaves on the
93 same wire. The bus master initiates all communication. The slaves can
94 be individually discovered and addressed using their unique ID.
95 Bus masters come in a variety of configurations including serial, par‐
97 allel, i2c, network or USB adapters.
98 OWFS design
100 OWFS is a suite of programs that designed to make the 1-wire bus and
101 its devices easily accessible. The underlying principle is to create a
102 virtual filesystem, with the unique ID being the directory, and the
103 individual properties of the device are represented as simple files
104 that can be read and written.
105 Details of the individual slave or master design are hidden behind a
107 consistent interface. The goal is to provide an easy set of tools for a
108 software designer to create monitoring or control applications. There
109 are some performance enhancements in the implementation, including data
110 caching, parallel access to bus masters, and aggregation of device com‐
111 munication. Still the fundemental goal has been ease of use, flexibil‐
112 ity and correctness rather than speed.
113 DS1995
115 The DS1995 (3) is an iButton with static memory. Data is read/written
116 with error checking (transparent to the user). The DS1992 , DS1993 ,
117 DS1995 , and DS1996 differ in their function by the amount of on-board
118 memory they possess. (The internal protocols are slightly different,
119 but the OWFS system handles this automatically.)
120
122 All 1-wire devices are factory assigned a unique 64-bit address. This
123 address is of the form:
124 Family Code
126 8 bits
127 Address
129 48 bits
130 CRC 8 bits
132 Addressing under OWFS is in hexidecimal, of form:
134 01.123456789ABC
136 where 01 is an example 8-bit family code, and 12345678ABC is an example
138 48 bit address.
139 The dot is optional, and the CRC code can included. If included, it
141 must be correct.
142
144 http://pdfserv.maxim-ic.com/en/ds/DS1995.pdf
145
147 Programs
148 owfs (1) owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1)
149 owwrite (1) owpresent (1) owtap (1)
150 Configuration and testing
152 owfs (5) owtap (1) owmon (1)
153 Language bindings
155 owtcl (3) owperl (3) owcapi (3)
156 Clocks
158 DS1427 (3) DS1904 (3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3)
159 DS2417 (3)
160 ID
162 DS2401 (3) DS2411 (3) DS1990A (3)
163 Memory
165 DS1982 (3) DS1985 (3) DS1986 (3) DS1991 (3) DS1992 (3) DS1993 (3)
166 DS1995 (3) DS1996 (3) DS2430A (3) DS2431 (3) DS2433 (3) DS2502 (3)
167 DS2506 (3) DS28E04 (3) DS28EC20 (3)
168 Switches
170 DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3)
171 Temperature
173 DS1822 (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3)
174 DS1921 (3) DS1821 (3) DS28EA00 (3) DS28E04 (3) EDS0064 (3) EDS0065 (3)
175 EDS0066 (3) EDS0067 (3) EDS0068 (3) EDS0071 (3) EDS0072 (3) MAX31826
176 [1m(3)
177 Humidity
179 DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)
180 Voltage
182 DS2450 (3)
183 Resistance
185 DS2890 (3)
186 Multifunction (current, voltage, temperature)
188 DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3)
189 DS2760 (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)
190 Counter
192 DS2423 (3)
193 LCD Screen
195 LCD (3) DS2408 (3)
196 Crypto
198 DS1977 (3)
199 Pressure
201 DS2406 (3) TAI8570 (3) EDS0066 (3) EDS0068 (3)
202 Moisture
204 EEEF (3) DS2438 (3)
205
207 http://www.owfs.org
208
210 Paul Alfille (paul.alfille@gmail.com)
211OWFS Manpage 2003 DS1995(3)