DS2401(3)

✨ NAME ✨

okay so bestie, say hi to the most babygirl little chip in the whole 1-wire family 💖. This is DS2401(3) from the One-Wire File System manual, and it is the basics: a serial number and nothing else. Iconic behaviour, honestly.

• DS2401 — Silicon Serial Number ✨
• DS1990A — Serial Number iButton 🎀

and the path shape it shows up as in the filesystem:

01 [.]XXXXXXXXXXXX[XX][/[ address | crc8 | id | locator | r_address | r_id | r_locator | type ]]

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🦋 SYNOPSIS 🦋

It's giving… a unique serial number. That's it. That's the whole personality. Unique serial number only.

🌈 FAMILY CODE 🌈

01

🎀 SPECIAL PROPERTIES 🎀

None. Not a single one. No cap.

💅 STANDARD PROPERTIES 💅

address / r_address

• read-only, ascii
• The entire 64-bit unique ID, written out as upper case hexadecimal digits (0-9A-F).
• address starts with the family code.
• r_address is the address in reverse order — which is the version other apps and labels love to use, iykyk.

crc8

• read-only, ascii
• The 8-bit error correction part. It uses cyclic redundancy check.
• It's computed from the preceding 56 bits of the unique ID number.
• Written as upper case hexadecimal digits (0-9A-F).

family

• read-only, ascii
• The 8-bit family code. Every type of device gets its own unique one.
• Written as upper case hexadecimal digits (0-9A-F).

id / r_id

• read-only, ascii
• The 48-bit middle chunk of the unique ID number. No family code, no CRC.
• Written as upper case hexadecimal digits (0-9A-F).
• r_id is the id in reverse order — again, the one other apps and labels reach for.

locator / r_locator

• read-only, ascii
• This one uses an extension of the 1-wire design from the iButtonLink company, which ties 1-wire physical connections to 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 there's no Link Locator 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?

Heads up bestie: this one is DEPRECATED. It still exists, but it's not the moment anymore.

type

• read-only, ascii
• The part name assigned by Dallas Semi. E.g. DS2401
• Alternative packaging (iButton vs chip) will not be distinguished. Same type, different fit. 🙈

🚨 ALARMS 🚨

None.

🌸 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. Power and data sharing one wire? Slay.

Each device is uniquely and unalterably numbered during manufacture. There's a wide variety of devices too, 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 principle 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. Filesystem as the interface? Obsessed.

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 fundamental goal has been ease of use, flexibility and correctness rather than speed.

DS2401 DS1990A

The DS2401 (3) and DS1990A (3) are the most basic of 1-wire devices. Their sole property is it's unique address. It can be used for unique identification. Nonetheless, many keylocks, night watchman systems, and tracking systems use this device.

🧚 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 included. If included, it must be correct.

Watch out: if you include that CRC, it has to be correct. No vibes-based CRCs, bestie.

📄 DATASHEET 📄

• http://pdfserv.maxim-ic.com/en/ds/DS2401.pdf
• http://pdfserv.maxim-ic.com/en/ds/DS1990A-F3-DS1990A-F5.pdf

👀 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)

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and that's the whole page, bestie 🫶 this one's from the OWFS Manpage, dated 2003. Go forth and read some serial numbers, you main character. periodt 💅✨