DS1995(3)

💖 DS1995 — 16kbit Memory iButton 💖

okay so bestie, this is a page from the One-Wire File System manual, section 3. Meet the DS1995, a 16kbit memory iButton. She's iconic, she's non-volatile, she remembers everything. 🧚

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🌸 NAME 🌸

DS1995 — the 16kbit Memory iButton. that's her. that's the whole name. 💅

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✨ SYNOPSIS ✨

Non-volatile memory. like she literally keeps it.

0A [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-63|ALL] | address |
crc8 | id | locator | r_address | r_id | r_locator | type ]]

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🎀 FAMILY CODE 🎀

• 0A — DS1996

(yes, that's what it says. we don't ask questions, we just report. 🙈)

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💅 SPECIAL PROPERTIES 💅

memory

read-write, binary. 2048 bytes of memory. that's a lot of bytes and she's using every one of them. 👑

pages/page.0 ... pages/page.63, pages/page.ALL

read-write, binary. the memory is split into 64 pages of 32 bytes each. ALL is an aggregate of the pages. each page is accessed sequentially — one at a time, in order, no cutting the line. 🚶♀️

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🫶 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 used in other applications and labeling. (it's giving "written backwards on purpose," iykyk.)

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). she checks herself before she wrecks herself. ✨

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 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 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?

⚠️ bestie this one is DEPRECATED. she's retired. still listed, still real, but she's on the way out. 💀

type

read-only, ascii.

part name assigned by Dallas Semi. e.g. DS2401. alternative packaging (iButton vs chip) will not be distinguished. same energy, different outfit. 🎀

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💀 ALARMS 💀

None.

that's it. no alarms. not a single one. she's chill like that. 😌

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🦋 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. yes, the data line is also the power line. multitasking queen. 💅

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 range?? unmatched. 🌈

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. like, you just read and write files. that's the whole vibe. 📁

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. correct > fast, always. periodt. ✨

DS1995

the DS1995 (3) is an iButton with static memory. data is read/written with error checking (transparent to the user). the DS1992, DS1993, DS1995, and DS1996 differ in their function by the amount of on-board memory they possess. (the internal protocols are slightly different, but the OWFS system handles this automatically.) so you don't have to think about it. she handles it. 👑

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🌈 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. no faking the CRC, bestie, she will notice. 😭

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📄 DATASHEET 📄

http://pdfserv.maxim-ic.com/en/ds/DS1995.pdf

go read the source material, it's giving academic. 🎓

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👑 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)

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⭐ AVAILABILITY ⭐

http://www.owfs.org

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💜 AUTHOR 💜

Paul Alfille (paul.alfille@gmail.com) — thank you for your service, king. 🫶

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and that's the whole page, bestie!! this came from the OWFS Manpage, dated 2003. slay, go read a DS1995 and tell her I said hi. 💖✨🦋🌸🎀