DS2406(3)

1DS2406(3)                    One-Wire File System                    DS2406(3)
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NAME

6       DS2406,  DS2407  -  Dual  Addressable Switch with 1kbit Memory, Hidable
7       Dual Addressable Switch with 1kbit Memory
8

SYNOPSIS

10       Dual Switch, Write-once Memory
11
12       12 [.]XXXXXXXXXXXX[XX][/[ channels | latch.[A|B|ALL|BYTE]  |  memory  |
13       pages/page.[0-3|ALL]     |     PIO.[A|B|ALL|BYTE]     |     power     |
14       sensed.[A|B|ALL|BYTE] | set_alarm |  TAI8570/[sibling|temperature|pres‐
15       sure]  | T8A/volt.[0-7,ALL] address | crc8 | id | locator | r_address |
16       r_id | r_locator | type ]]
17

FAMILY CODE

19       12
20

SPECIAL PROPERTIES

22   channels
23       read-only, unsigned integer
24       Is this a 1 or 2 channel switch? The DS2406 comes in two forms, one has
25       only one PIO pin (PIO.A). Returns 1 or 2.
26
27   latch.A latch.B latch.ALL latch.BYTE
28       read-write, yes-no
29       The activity latch is set to 1 with the first negative or positive edge
30       detected on the associated PIO channel.
31       Writing any data will clear latch for all (both)) channels. This  is  a
32       hardware "feature" of the chip.
33       ALL references both channels simultaneously, comma separated
34       BYTE  references  both  channels  simultaneously as a single byte, with
35       channel A in bit 0.
36
37   memory
38       read-write, binary
39       128 bytes of non-volatile, write-once data.
40
41   pages/page.0 ... pages/page.3 pages/page.ALL
42       read-write, binary
43       Memory organized as 4 pages or 32 bytes. Memory is write-once.
44       ALL is the aggregate of all 4 pages, sequentially accessed.
45
46   PIO.A PIO.B PIO.ALL PIO.BYTE
47       read-write, yes-no
48       State of the open-drain output ( PIO ) pin. 0 = non-conducting (off), 1
49       = conducting (on).
50       Writing  zero  will  turn  off  the  switch,  non-zero will turn on the
51       switch. Reading the PIO state will return the switch setting  (flipflop
52       in  the data sheet). To determine the actual logic level at the switch,
53       refer to the sensed property.
54       Note that the actual pin setting for the chip uses the opposite  polar‐
55       ity  -- 0 for conducting, 1 for non-conducting. However, to turn a con‐
56       nected device on (i.e. to deliver power) we use the software concept of
57       1 as conducting or "on".
58       ALL references both channels simultaneously, comma separated.
59       BYTE  references  both  channels  simultaneously as a single byte, with
60       channel A in bit 0.
61
62   power
63       read-only, yes-no
64       Is the DS2406 powered parasitically =0 or separately on the Vcc pin =1
65
66   sensed.A sensed.B sensed.ALL sensed.BYTE
67       read-only, yes-no
68       Logic level at the PIO pin. 0 = ground. 1 = high (~2.4V - 5V ).  Really
69       makes  sense only if the PIO state is set to zero (off), else will read
70       zero.
71       ALL references both channels simultaneously, comma separated.
72       BYTE references both channels simultaneously as  a  single  byte,  with
73       channel A in bit 0.
74
75   set_alarm
76       read-write, unsigned integer (0-331)
77       A number consisting of three digits XYZ, where:
78
79       X      channel selection
80              0 neither
81              1 A only
82              2 B only
83              3 A or B
84
85       Y      source selection
86              0 undefined
87              1 latch
88              2 PIO
89              3 sensed
90
91       Z      polarity selection
92              0 low
93              1 high
94
95       All  digits will be truncated to the 0-3 (or 0-1) range. Leading zeroes
96       are optional (and may be problematic for some shells).
97
98       Example:
99
100       311    Responds on Conditional Search when either  latch.A  or  latch.B
101              (or both) are set to 1.
102
103       <100   Never responds to Conditional Search.
104
105   TAI8570/
106       subdirectory
107       Properties when the DS2406 [4m(3) is built into a TAI8570.
108       If  the  DS2406  [4m(3) is not part of a TAI8570 or is not the controlling
109       switch, attempts to read will result in an error.
110
111   TAI8570/pressure
112       read-only, floating point
113       Barometric pressure in millibar.
114
115   TAI8570/sibling
116       read-only, ascii
117       Hex address of the DS2406 [4m(3) paired with this chip in a TAI8570.
118
119   TAI8570/temperature
120       read-only, floating-point
121       Ambient temperature measured by the TAI8570 in  prevailing  temperature
122       units (Centigrade is the default).
123
124   T8A/volt.[0-7|ALL]
125       read-only, floating-point
126       Uses  the  T8A (by Embedded Data Systems ) 8 channel voltage converter.
127       Units in volts, 0 to 5V range. 12 bit resolution.
128

STANDARD PROPERTIES

130   address
131   r_address
132       read-only, ascii
133       The entire 64-bit unique ID. Given as  upper  case  hexidecimal  digits
134       (0-9A-F).
135       address starts with the family code
136       r address is the address in reverse order, which is often used in other
137       applications and labeling.
138
139   crc8
140       read-only, ascii
141       The 8-bit error correction portion. Uses cyclic redundancy check.  Com‐
142       puted  from  the  preceding  56  bits of the unique ID number. Given as
143       upper case hexadecimal digits (0-9A-F).
144
145   family
146       read-only, ascii
147       The 8-bit family code. Unique to each type of device.  Given  as  upper
148       case hexadecimal digits (0-9A-F).
149
150   id
151   r_id
152       read-only, ascii
153       The 48-bit middle portion of the unique ID number. Does not include the
154       family code or CRC. Given as upper case hexadecimal digits (0-9A-F).
155       r id is the id in reverse order, which is often used in other  applica‐
156       tions and labeling.
157
158   locator
159   r_locator
160       read-only, ascii
161       Uses  an  extension  of the 1-wire design from iButtonLink company that
162       associated 1-wire physical connections with a unique  1-wire  code.  If
163       the  connection is behind a Link Locator the locator will show a unique
164       8-byte number (16 character hexadecimal) starting with family code FE.
165       If no Link Locator is between the device and the  master,  the  locator
166       field will be all FF.
167       r locator is the locator in reverse order.
168
169   present (DEPRECATED)
170       read-only, yes-no
171       Is the device currently present on the 1-wire bus?
172
173   type
174       read-only, ascii
175       Part  name  assigned by Dallas Semi. E.g.  DS2401 Alternative packaging
176       (iButton vs chip) will not be distiguished.
177

ALARMS

179       Use the set_alarm property to set the alarm triggering criteria.
180

DESCRIPTION

182   1-Wire
183       1-wire is a wiring protocol and series of devices designed and manufac‐
184       tured  by  Dallas  Semiconductor, Inc. The bus is a low-power low-speed
185       low-connector scheme where the data line can also provide power.
186
187       Each device is uniquely and unalterably  numbered  during  manufacture.
188       There  are a wide variety of devices, including memory, sensors (humid‐
189       ity, temperature, voltage, contact, current), switches, timers and data
190       loggers.  More complex devices (like thermocouple sensors) can be built
191       with these basic devices. There  are  also  1-wire  devices  that  have
192       encryption included.
193
194       The  1-wire  scheme uses a single bus master and multiple slaves on the
195       same wire. The bus master initiates all communication. The  slaves  can
196       be individually discovered and addressed using their unique ID.
197
198       Bus  masters come in a variety of configurations including serial, par‐
199       allel, i2c, network or USB adapters.
200
201   OWFS design
202       OWFS is a suite of programs that designed to make the  1-wire  bus  and
203       its  devices easily accessible. The underlying principle is to create a
204       virtual filesystem, with the unique ID being  the  directory,  and  the
205       individual  properties  of  the  device are represented as simple files
206       that can be read and written.
207
208       Details of the individual slave or master design are  hidden  behind  a
209       consistent interface. The goal is to provide an easy set of tools for a
210       software designer to create monitoring or control  applications.  There
211       are some performance enhancements in the implementation, including data
212       caching, parallel access to bus masters, and aggregation of device com‐
213       munication.  Still the fundamental goal has been ease of use, flexibil‐
214       ity and correctness rather than speed.
215
216   DS2406
217       The DS2406 (3) allows control of other devices, like LEDs  and  relays.
218       It  superceeds  the  DS2405 and DS2407 Alternative switches include the
219       DS2408 or even DS2450
220       The DS2407 is practically identical to the DS2406 except for a  strange
221       hidden mode. It is supported just like the DS2406
222
223   TAI8570
224       The  TAI-8570  Pressure Sensor is based on a 1-wire composite device by
225       AAG Electronica.  The TAI8570 uses 2 DS2406  [4m(3)  chips,  paired  as  a
226       reader  and  writer  to  synthesize 3-wire communication. Only 1 of the
227       DS2406 [4m(3) will allow temperature or  pressure  readings.  It's  mate's
228       address can be shown as sibling.
229
230       The TAI8570 uses the Intersema MS5534a pressure sensor, and stores cal‐
231       ibration and temperature compensation values internally.
232
233       Design  and  code  examples  are   available   from   AAG   Electronica
234       http://aag.com.mx  ,  specific  permission to use code in a GPL product
235       was given by Mr. Aitor Arrieta of AAG and Dr. Simon Melhuish of OWW.
236

ADDRESSING

238       All 1-wire devices are factory assigned a unique 64-bit  address.  This
239       address is of the form:
240
241       Family Code
242              8 bits
243
244       Address
245              48 bits
246
247       CRC    8 bits
248
249       Addressing under OWFS is in hexadecimal, of form:
250
251              01.123456789ABC
252
253       where 01 is an example 8-bit family code, and 12345678ABC is an example
254       48 bit address.
255
256       The dot is optional, and the CRC code can  included.  If  included,  it
257       must be correct.
258

DATASHEET

260       http://pdfserv.maxim-ic.com/en/ds/DS2406.pdf
261       http://pdfserv.maxim-ic.com/en/ds/DS2407.pdf
262       http://www.embeddeddatasystems.com/page/EDS/PROD/IO/T8A
263       http://oww.sourceforge.net/hardware.html#bp
264

AVAILABILITY

326       http://www.owfs.org
327

AUTHOR

329       Paul Alfille (paul.alfille@gmail.com)
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333OWFS Manpage                         2003                            DS2406(3)