1DS2436(3) One-Wire File System DS2436(3)
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6 DS2436 - Battery ID/Monitor Chip
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9 Temperature Voltage and Memory.
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11 1B [.]XXXXXXXXXXXX[XX][/[ pages/page.[0-4|ALL] | temperature | volts |
12 counter/cycles | counter/reset | counter/increment | address | crc8 |
13 id | locator | r_address | r_id | r_locator | type ]]
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16 1B
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19 pages/page.0 ... pages/page.4 pages/page.ALL
20 read-write, binary
21 Memory is split into 5 pages of 32 bytes each. Only the first 3 pages
22 are really available, and some of that appears to be reserved. See the
23 datasheet for details.
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25 pages/page.0 is locked and unlocked transparently for every write.
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27 ALL is an aggregate of the pages. Each page is accessed sequentially.
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29 temperature
30 read-only, floating point
31 Temperature read by the chip at high resolution (~13 bits). Units are
32 selected from the invoking command line. See owfs(1) or owhttpd(1) for
33 choices. Default is Celsius. Conversion takes ~20 msec.
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35 volts
36 read-only, floating point
37 Voltage read (~10 bits) at the chip's supply voltage Vdd. Range 2.4V to
38 10V.
39
40 counter/
41 A resettable non-volatile counter intended for counting battery dis‐
42 charge cycles.
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44 counter/cycles
45 read-only, unsigned integer
46 Cycle counter value. Stored at memory location 0x82.
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48 counter/increment
49 write-only, yes/no
50 Any non-zero (true) value will increment counter/cycles by one.
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52 counter/reset
53 write-only, yes/no
54 Any non-zero (true) value will reset counter/cycles to zero.
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57 address
58 r_address
59 read-only, ascii
60 The entire 64-bit unique ID. Given as upper case hexadecimal digits
61 (0-9A-F).
62 address starts with the family code
63 r address is the address in reverse order, which is often used in other
64 applications and labeling.
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66 crc8
67 read-only, ascii
68 The 8-bit error correction portion. Uses cyclic redundancy check. Com‐
69 puted from the preceding 56 bits of the unique ID number. Given as up‐
70 per case hexadecimal digits (0-9A-F).
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72 family
73 read-only, ascii
74 The 8-bit family code. Unique to each type of device. Given as upper
75 case hexadecimal digits (0-9A-F).
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77 id
78 r_id
79 read-only, ascii
80 The 48-bit middle portion of the unique ID number. Does not include the
81 family code or CRC. Given as upper case hexadecimal digits (0-9A-F).
82 r id is the id in reverse order, which is often used in other applica‐
83 tions and labeling.
84
85 locator
86 r_locator
87 read-only, ascii
88 Uses an extension of the 1-wire design from iButtonLink company that
89 associated 1-wire physical connections with a unique 1-wire code. If
90 the connection is behind a Link Locator the locator will show a unique
91 8-byte number (16 character hexadecimal) starting with family code FE.
92 If no Link Locator is between the device and the master, the locator
93 field will be all FF.
94 r locator is the locator in reverse order.
95
96 present (DEPRECATED)
97 read-only, yes-no
98 Is the device currently present on the 1-wire bus?
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100 type
101 read-only, ascii
102 Part name assigned by Dallas Semi. E.g. DS2401 Alternative packaging
103 (iButton vs chip) will not be distiguished.
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106 None.
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109 1-Wire
110 1-wire is a wiring protocol and series of devices designed and manufac‐
111 tured by Dallas Semiconductor, Inc. The bus is a low-power low-speed
112 low-connector scheme where the data line can also provide power.
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114 Each device is uniquely and unalterably numbered during manufacture.
115 There are a wide variety of devices, including memory, sensors (humid‐
116 ity, temperature, voltage, contact, current), switches, timers and data
117 loggers. More complex devices (like thermocouple sensors) can be built
118 with these basic devices. There are also 1-wire devices that have en‐
119 cryption included.
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121 The 1-wire scheme uses a single bus master and multiple slaves on the
122 same wire. The bus master initiates all communication. The slaves can
123 be individually discovered and addressed using their unique ID.
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125 Bus masters come in a variety of configurations including serial, par‐
126 allel, i2c, network or USB adapters.
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128 OWFS design
129 OWFS is a suite of programs that designed to make the 1-wire bus and
130 its devices easily accessible. The underlying principle is to create a
131 virtual filesystem, with the unique ID being the directory, and the in‐
132 dividual properties of the device are represented as simple files that
133 can be read and written.
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135 Details of the individual slave or master design are hidden behind a
136 consistent interface. The goal is to provide an easy set of tools for a
137 software designer to create monitoring or control applications. There
138 are some performance enhancements in the implementation, including data
139 caching, parallel access to bus masters, and aggregation of device com‐
140 munication. Still the fundamental goal has been ease of use, flexibil‐
141 ity and correctness rather than speed.
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143 DS2436
144 The DS2436 (3) is a simpler form of the DS2438 battery chip. It has no
145 counter, and only one voltage sensor.
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148 All 1-wire devices are factory assigned a unique 64-bit address. This
149 address is of the form:
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151 Family Code
152 8 bits
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154 Address
155 48 bits
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157 CRC 8 bits
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159 Addressing under OWFS is in hexadecimal, of form:
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161 01.123456789ABC
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163 where 01 is an example 8-bit family code, and 12345678ABC is an example
164 48 bit address.
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166 The dot is optional, and the CRC code can included. If included, it
167 must be correct.
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170 http://pdfserv.maxim-ic.com/en/ds/DS2436.pdf
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173 Programs
174 owfs (1) owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1)
175 owwrite (1) owpresent (1) owtap (1)
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177 Configuration and testing
178 owfs (5) owtap (1) owmon (1)
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180 Language bindings
181 owtcl (3) owperl (3) owcapi (3)
182
183 Clocks
184 DS1427 (3) DS1904 (3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3)
185 DS2417 (3)
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187 ID
188 DS2401 (3) DS2411 (3) DS1990A (3)
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190 Memory
191 DS1982 (3) DS1985 (3) DS1986 (3) DS1991 (3) DS1992 (3) DS1993 (3)
192 DS1995 (3) DS1996 (3) DS2430A (3) DS2431 (3) DS2433 (3) DS2502 (3)
193 DS2506 (3) DS28E04 (3) DS28EC20 (3)
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195 Switches
196 DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3) In‐
197 fernoEmbedded (3)
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199 Temperature
200 DS1822 (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3)
201 DS1921 (3) DS1821 (3) DS28EA00 (3) DS28E04 (3) EDS0064 (3) EDS0065 (3)
202 EDS0066 (3) EDS0067 (3) EDS0068 (3) EDS0071 (3) EDS0072 (3) MAX31826
203 [1m(3)
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205 Humidity
206 DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)
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208 Voltage
209 DS2450 (3)
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211 Resistance
212 DS2890 (3)
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214 Multifunction (current, voltage, temperature)
215 DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3)
216 DS2760 (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)
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218 Counter
219 DS2423 (3)
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221 LCD Screen
222 LCD (3) DS2408 (3)
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224 Crypto
225 DS1977 (3)
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227 Pressure
228 DS2406 (3) TAI8570 (3) EDS0066 (3) EDS0068 (3)
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230 Moisture
231 EEEF (3) DS2438 (3)
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234 http://www.owfs.org
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237 Paul Alfille (paul.alfille@gmail.com)
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241OWFS Manpage 2003 DS2436(3)