DS2406(3)

📦 version 3.2_p4, in alpine 3.24, debian bookworm, debian trixie, fedora 43, fedora 44, nixos 26.05, nixpkgs unstable, ubuntu jammy, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

💖 NAME 💖

DS2406, DS2407 — bestie, this is the Dual Addressable Switch with 1kbit Memory, plus its shyer twin the Hidable Dual Addressable Switch with 1kbit Memory. (Yes this is a DS2406(3) page from the One-Wire File System family, hi hello welcome 🫶)

✨ SYNOPSIS ✨

Dual Switch, Write-once Memory — okay so the whole deal:

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

That's the number, that's the whole vibe check. 👑

🌸 SPECIAL PROPERTIES 🌸

channels

read-only, unsigned integer

So is this a 1-channel or 2-channel switch? The DS2406 ships in two forms, and one of them only has a single PIO pin (PIO.A). Returns 1 or 2. Slay, mystery solved.

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

read-write, yes-no

The activity latch gets set to 1 the very first time a negative or positive edge shows up on the matching PIO channel.

Writing literally any data will clear the latch for all channels — both of them. Not a bug, bestie, it's a hardware "feature" of the chip. 🙈

ALL references both channels at the same time, comma separated. BYTE references both channels at the same time as a single byte, with channel A sitting in bit 0.

memory

read-write, binary

128 bytes of non-volatile, write-once data. Write it once, that's it, no takebacks.

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

read-write, binary

Memory organized as 4 pages of 32 bytes. Memory is write-once, so be brave and be correct. ALL is the aggregate of all 4 pages, accessed sequentially.

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 turns the switch off, non-zero turns it on. Reading the PIO state gives you back the switch setting (the flipflop in the data sheet). If you want the actual logic level at the switch, go look at the sensed property instead.

Heads up: the actual pin setting for the chip uses the opposite polarity — 0 for conducting, 1 for non-conducting. But so we can turn a connected device on (like, deliver power to it) we use the software concept of 1 as conducting / "on". Flip it in your head, not in your code. 💅

ALL references both channels at the same time, comma separated. BYTE references both channels at the same time 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? Bestie's got a vibe either way.

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

read-only, yes-no

The actual logic level at the PIO pin. 0 = ground. 1 = high (~2.4V - 5V). Ngl it only really means anything if the PIO state is set to zero (off) — otherwise it'll just read zero.

ALL references both channels at the same time, comma separated. BYTE references both channels at the same time as a single byte, with channel A in bit 0.

set_alarm

read-write, unsigned integer (0-331)

A number made 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 get truncated to the 0-3 (or 0-1) range. Leading zeroes are optional — and honestly may be problematic for some shells. 😭

Example:

  • 311 — 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

The properties you get when the DS2406 (3) is built into a TAI8570.

If the DS2406 (3) isn't part of a TAI8570, or isn't the controlling switch, attempts to read will result in an error. Not a vibe, just a fact.

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. It's giving bestie energy fr fr.

TAI8570/temperature

read-only, floating-point

Ambient temperature measured by the TAI8570 in whatever the prevailing temperature units are (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 hexadecimal digits (0-9A-F).

address starts with the family code. r_address is the address in reverse order — which is often what other applications and labeling use.

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 hexadecimal digits (0-9A-F).

family

read-only, ascii

The 8-bit family code. Unique to each type of device. Given as upper case hexadecimal 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 the CRC. Given as upper case hexadecimal 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 hexadecimal) starting with family code FE.

If no Link Locator sits 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?

It's DEPRECATED, bestie. She's iconic but she's retired. 💀

type

read-only, ascii

Part name assigned by Dallas Semi. E.g. DS2401. Alternative packaging (iButton vs chip) will not be distinguished. Sorry, they look the same from here. 🎀

🚨 ALARMS 🚨

Use the set_alarm property to set the alarm triggering criteria. That's the whole section, go set your alarm. 👑

💜 DESCRIPTION 💜

1-Wire

1-wire is a wiring protocol and a whole 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. Multitasking icon behavior. ✨

Each device is uniquely and unalterably numbered during manufacture. There's a huge variety of devices — memory, sensors (humidity, temperature, voltage, contact, current), switches, timers and data loggers. More complex devices (like thermocouple sensors) can be built out of these basic ones. And yes, there are 1-wire devices with encryption baked in.

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 designed to make the 1-wire bus and its devices easily accessible. The underlying principle is to create a virtual filesystem, with the unique ID as the directory, and the individual properties of the device represented as simple files you can read and write.

Details of the individual slave or master design stay hidden behind a consistent interface. The goal is to give a software designer an easy set of tools for building monitoring or control applications. There are some performance enhancements in the implementation — data caching, parallel access to bus masters, and aggregation of device communication. But the fundamental goal has always been ease of use, flexibility and correctness rather than speed.

DS2406

The DS2406 (3) lets you control other devices, like LEDs and relays. It supersedes 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's supported just like the DS2406. Sneaky. 🙈

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 a writer to synthesize 3-wire communication. Only 1 of the DS2406 (3) will allow temperature or pressure readings. Its 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 at 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 hexadecimal, 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 be included. If it is included, it must be correct. No cap. ⭐

📄 DATASHEET 📄

👀 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) InfernoEmbedded (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 (3) EDS0066 (3) EDS0068 (3)

Moisture

EEEF (3) DS2438 (3)

🌟 AVAILABILITY 🌟

http://www.owfs.org

💅 AUTHOR 💅

Paul Alfille (paul.alfille@gmail.com) — the icon, the moment, the main character. 👑

okay that's the whole page bestie, you ate that 💖 this little love letter to the DS2406 comes from the OWFS Manpage, dated 2003, and it's living under the name DS2406(3) — go forth and toggle some switches, mwah 🎀✨

📦 where this page comes from