1DS2431(3) One-Wire File System DS2431(3)
2
6 DS2431 - EEPROM (1 kBit)
7
9 Erasable programmable read-only memory (EEPROM)
10 2D [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-3|ALL] | address |
12 crc8 | id | locator | r_address | r_id | r_locator | type ]]
13
15 2D DS2431
16
18 memory
19 read-write, binary
20 128 bytes of EEPROM memory. Initially all bits are set to 1. Memory is
21 non-volatile.
22 pages/page.0 ... pages/page.3 pages/page.ALL
24 read-write, yes-no
25 Memory is split into 4 pages of 32 bytes each. ALL is an aggregate of
26 the pages. Each page is accessed sequentially.
27
29 address
30 r_address
31 read-only, ascii
32 The entire 64-bit unique ID. Given as upper case hexadecimal digits
33 (0-9A-F).
34 address starts with the family code
35 r address is the address in reverse order, which is often used in other
36 applications and labeling.
37 crc8
39 read-only, ascii
40 The 8-bit error correction portion. Uses cyclic redundancy check. Com‐
41 puted from the preceding 56 bits of the unique ID number. Given as up‐
42 per case hexadecimal digits (0-9A-F).
43 family
45 read-only, ascii
46 The 8-bit family code. Unique to each type of device. Given as upper
47 case hexadecimal digits (0-9A-F).
48 id
50 r_id
51 read-only, ascii
52 The 48-bit middle portion of the unique ID number. Does not include the
53 family code or CRC. Given as upper case hexadecimal digits (0-9A-F).
54 r id is the id in reverse order, which is often used in other applica‐
55 tions and labeling.
56 locator
58 r_locator
59 read-only, ascii
60 Uses an extension of the 1-wire design from iButtonLink company that
61 associated 1-wire physical connections with a unique 1-wire code. If
62 the connection is behind a Link Locator the locator will show a unique
63 8-byte number (16 character hexadecimal) starting with family code FE.
64 If no Link Locator is between the device and the master, the locator
65 field will be all FF.
66 r locator is the locator in reverse order.
67 present (DEPRECATED)
69 read-only, yes-no
70 Is the device currently present on the 1-wire bus?
71 type
73 read-only, ascii
74 Part name assigned by Dallas Semi. E.g. DS2401 Alternative packaging
75 (iButton vs chip) will not be distiguished.
76
78 None.
79
81 1-Wire
82 1-wire is a wiring protocol and series of devices designed and manufac‐
83 tured by Dallas Semiconductor, Inc. The bus is a low-power low-speed
84 low-connector scheme where the data line can also provide power.
85 Each device is uniquely and unalterably numbered during manufacture.
87 There are a wide variety of devices, including memory, sensors (humid‐
88 ity, temperature, voltage, contact, current), switches, timers and data
89 loggers. More complex devices (like thermocouple sensors) can be built
90 with these basic devices. There are also 1-wire devices that have en‐
91 cryption included.
92 The 1-wire scheme uses a single bus master and multiple slaves on the
94 same wire. The bus master initiates all communication. The slaves can
95 be individually discovered and addressed using their unique ID.
96 Bus masters come in a variety of configurations including serial, par‐
98 allel, i2c, network or USB adapters.
99 OWFS design
101 OWFS is a suite of programs that designed to make the 1-wire bus and
102 its devices easily accessible. The underlying principle is to create a
103 virtual filesystem, with the unique ID being the directory, and the in‐
104 dividual properties of the device are represented as simple files that
105 can be read and written.
106 Details of the individual slave or master design are hidden behind a
108 consistent interface. The goal is to provide an easy set of tools for a
109 software designer to create monitoring or control applications. There
110 are some performance enhancements in the implementation, including data
111 caching, parallel access to bus masters, and aggregation of device com‐
112 munication. Still the fundamental goal has been ease of use, flexibil‐
113 ity and correctness rather than speed.
114 DS2431
116 The DS2431 (3) is used for storing memory which should be available
117 even after a reset or power off. It is also switch to erase-only mode
118 (EPROM) although this isn't implemented in OWFS. OWFS system handles
119 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 hexadecimal, 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/DS2431.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) In‐
171 fernoEmbedded (3)
172 Temperature
174 DS1822 (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3)
175 DS1921 (3) DS1821 (3) DS28EA00 (3) DS28E04 (3) EDS0064 (3) EDS0065 (3)
176 EDS0066 (3) EDS0067 (3) EDS0068 (3) EDS0071 (3) EDS0072 (3) MAX31826
177 [1m(3)
178 Humidity
180 DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)
181 Voltage
183 DS2450 (3)
184 Resistance
186 DS2890 (3)
187 Multifunction (current, voltage, temperature)
189 DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3)
190 DS2760 (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)
191 Counter
193 DS2423 (3)
194 LCD Screen
196 LCD (3) DS2408 (3)
197 Crypto
199 DS1977 (3)
200 Pressure
202 DS2406 (3) TAI8570 (3) EDS0066 (3) EDS0068 (3)
203 Moisture
205 EEEF (3) DS2438 (3)
206
208 http://www.owfs.org
209
211 Christian Magnusson (mag@mag.cx)
212OWFS Manpage 2003 DS2431(3)