Table of Contents

Name

DS2406
Dual Addressable Switch with 1kbit Memory
DS2407
Hidable Dual Addressable Switch with 1kbit Memory

Synopsis

Dual Switch, Write-once Memory

12 [.]XXXXXXXXXXXX[XX][/[ channels | latch.[A|B|ALL|BYTE] | memory | pages/page.[0-3|ALL] | PIO.[A|B|ALL|BYTE] | power | sensed.[A|B|ALL|BYTE] | set_alarm | TAI8570/[sibling|temperature|pressure] | T8A/volt.[0-7,ALL] address | crc8 | id | locator | r_address | r_id | r_locator | type ]]

Family Code

12

Special Properties

channels

read-only, unsigned integer
Is this a 1 or 2 channel switch? The DS2406 comes in two forms, one has only one PIO pin (PIO.A). Returns 1 or 2.

latch.A latch.B latch.ALL latch.BYTE

read-write, yes-no
The activity latch is set to 1 with the first negative or positive edge detected on the associated PIO channel.
Writing any data will clear latch for all (both)) channels. This is a hardware "feature" of the chip.
ALL references both channels simultaneously, comma separated
BYTE references both channels simultaneously as a single byte, with channel A in bit 0.

memory

read-write, binary
128 bytes of non-volatile, write-once data.

pages/page.0 ... pages/page.3 pages/page.ALL

read-write, binary
Memory organized as 4 pages or 32 bytes. Memory is write-once.
ALL is the aggregate of all 4 pages, sequentially accessed.

Pio.a Pio.b Pio.all Pio.byte

read-write, yes-no
State of the open-drain output ( PIO ) pin. 0 = non-conducting (off), 1 = conducting (on) .
Writing zero will turn off the switch, non-zero will turn on the switch. Reading the PIO state will return the switch setting (flipflop in the data sheet). To determine the actual logic level at the switch, refer to the sensed property.
Note that the actual pin setting for the chip uses the opposite polarity -- 0 for conducting, 1 for non-conducting. However, to turn a connected device on (i.e. to deliver power) we use the software concept of 1 as conducting or "on".
ALL references both channels simultaneously, comma separated.
BYTE references both channels simultaneously as a single byte, with channel A in bit 0.

power

read-only, yes-no
Is the DS2406 powered parasitically =0 or separately on the Vcc pin =1

sensed.A sensed.B sensed.ALL sensed.BYTE

read-only, yes-no
Logic level at the PIO pin. 0 = ground. 1 = high (~2.4V - 5V ). Really makes sense only if the PIO state is set to zero (off), else will read zero.
ALL references both channels simultaneously, comma separated.
BYTE references both channels simultaneously as a single byte, with channel A in bit 0.

set_alarm

read-write, unsigned integer (0-331)
A number consisting of three digits XYZ, where:
X
channel selection
0 neither
1 A only
2 B only
3 A or B
Y
source selection
0 undefined
1 latch
2 PIO
3 sensed
Z
polarity selection
0 low
1 high

All digits will be truncated to the 0-3 (or 0-1) range. Leading zeroes are optional (and may be problematic for some shells).

Example:

  1. Responds on Conditional Search when either latch.A or latch.B (or both) are set to 1.
    <100
    Never responds to Conditional Search.

    Tai8570/

    subdirectory
    Properties when the DS2406 (3) is built into a TAI8570.
    If the DS2406 (3) is not part of a TAI8570 or is not the controlling switch, attempts to read will result in an error.

    TAI8570/pressure

    read-only, floating point
    Barometric pressure in millibar.

    TAI8570/sibling

    read-only, ascii
    Hex address of the DS2406 (3) paired with this chip in a TAI8570.

    TAI8570/temperature

    read-only, floating-point
    Ambient temperature measured by the TAI8570 in prevailing temperature units (Centigrade is the default).

    T8A/volt.[0-7|ALL]

    read-only, floating-point
    Uses the T8A (by Embedded Data Systems ) 8 channel voltage converter. Units in volts, 0 to 5V range. 12 bit resolution.

    Standard Properties

    address

    r_address

    read-only, ascii
    The entire 64-bit unique ID. Given as upper case hexidecimal 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 hexidecimal digits (0-9A-F).

    family

    read-only, ascii
    The 8-bit family code. Unique to each type of device. Given as upper case hexidecimal 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 hexidecimal 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 hexidecimal) 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

    Use the set_alarm property to set the alarm triggering criteria.

    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 priciple 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.

    Ds2406

    The DS2406 (3) allows control of other devices, like LEDs and relays. It superceeds the DS2405 and DS2407 Alternative switches include the DS2408 or even DS2450
    The DS2407 is practically identical to the DS2406 except for a strange hidden mode. It is supported just like the DS2406

    Tai8570

    The TAI-8570 Pressure Sensor is based on a 1-wire composite device by AAG Electronica. The TAI8570 uses 2 DS2406 (3) chips, paired as a reader and writer to synthesize 3-wire communication. Only 1 of the DS2406 (3) will allow temperature or pressure readings. It’s mate’s address can be shown as sibling.

    The TAI8570 uses the Intersema MS5534a pressure sensor, and stores calibration and temperature compensation values internally.

    Design and code examples are available from AAG Electronica http://aag.com.mx , specific permission to use code in a GPL product was given by Mr. Aitor Arrieta of AAG and Dr. Simon Melhuish of OWW.

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

    See Also

    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 EDS0066 (3) EDS0068 (3)

    Moisture

    EEEF (3) DS2438 (3)

    Availability

    http://www.owfs.org

    Author

    Paul Alfille (paul.alfille@gmail.com)


    Table of Contents