DS2404(3)

✨ NAME ✨

okay so bestie, let me introduce you to the whole clock-and-memory girlie squad 💖 this manpage is about four devices that are basically the same vibe in different outfits:

• DS2404 — EconoRAM time chip 🕐
• DS2404S — Dual port memory plus time
• DS1994 — 4k plus time iButton
• DS1427 — Time iButton

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🔌 SYNOPSIS 🔌

Real time clock, 4kbit memory. 3-wire interface, too. (yes she does both, she's versatile 💅)

04.XXXXXXXXXXXX / alarm | auto | cycle | date | delay | interval |
memory | pages/page.[0-15|ALL] | readonly/[memory|clock|cycle|interval]
| memory | pages/page.[0-15|ALL] |
readonly/[memory|clock|cycle|interval] | running | set_alarm | start |
trigger/[cycle,date,interval,udate,uinterval] | udate | uinterval |
address | crc8 | id | locator | r_address | r_id | r_locator | type

84.XXXXXXXXXXXX / alarm | auto | cycle | date | delay | interval |
memory | pages/page.[0-15|ALL] | readonly/[memory|clock|cycle|interval]
| running | set_alarm | start |
trigger/[cycle,date,interval,udate,uinterval] | udate | uinterval |
address | crc8 | id | present | type

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👑 FAMILY CODE 👑

04     DS2404 DS1994

84     DS1427 DS2404S

that's the family code, it's like the last name of the device, iconic 🌈

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🎀 SPECIAL PROPERTIES 🎀

these are the properties that make these chips them, the main character energy ones 🫶

alarm

read-write, unsigned integer (0-111)

Alarm state of the DS2404 (3) triggered by time or counter events. Reading the alarm state clears the alarm — so like, read it and it's gone, no takebacks 😭

The alarm value is of the form CIR, where:

• C — cycle counter alarm
  • 0 no
  • 1 yes
• I — interval timer alarm
  • 0 no
  • 1 yes
• R — real-time clock alarm
  • 0 no
  • 1 yes

auto

read-write, yes-no

Flag for mode of interval counter operation. 0=manual 1=auto

See the datasheet for details. (iykyk)

date

read-write, ascii

26 character date representation of the udate value. Increments once per second while running.

Actual internal representation has higher precision — she's giving more than she shows, lowkey ✨

Cannot be altered if readonly/clock is set.

Setting date to a null string will put the current system time.

Accepted date formats are:

Sat[urday] March 12 12:23:59 2001
Apr[il] 4 9:34:56 2002
3/23/04 23:34:57
current locale setting (your system's format)

delay

read-write, yes-no

Flag for adding a delay to cycle counter. 0=short 1-long

See the datasheet under "IDEL" for details.

interval

read-write, date

Interval timer value, represented as a date string. More typically will be used as uinterval to read the actual elapsed seconds.

memory

read-write, binary

512 bytes of memory. The readonly/memory flag prevents further change. once you lock her down she stays locked, periodt 💀

pages/page.0 ... pages/page.15 pages/page.ALL

read-write, yes-no

Memory is split into 16 pages of 32 bytes each. The readonly/memory flag prevents further change. ALL is an aggregate of the pages. Each page is accessed sequentially.

readonly/[memory|clock|interval|cycle]

read-write, yes-no

Permanently protect part of the chip's function from alteration. Permanently, bestie — like, no undo, no ctrl+z, no nothing 🙈

• readonly/memory — page.X and memory
• readonly/clock — date and udate
• readonly/interval — interval
• readonly/cycle — cycle

running

read-write, yes-no

State of the clock. 0=off 1=running.

set_alarm

read-write, unsigned integer (0-111)

Which of the alarm triggers are enabled in the DS2404 (3)

The set_alarm value is of the form CIR, where:

• C — cycle counter alarm
  • 0 no
  • 1 yes
• I — interval timer alarm
  • 0 no
  • 1 yes
• R — real-time clock alarm
  • 0 no
  • 1 yes

start

read-write, yes-no

Flag for starting the interval counter operation if not in auto mode. 0=stop 1=start

See the datasheet for details.

trigger/[cycle,date,interval,udate,uinterval]

read-write,varies

Target value that will trigger the alarm if the corresponding set_alarm field is set.

The format is the same as the similarly named field (i.e. date for trigger/date )

udate

read-write, unsigned integer

Time represented as a number. udate increments once per second, while running is on.

Usually set to unix time standard: number of seconds since Jan 1, 1970.

The date field will be the unix representation of udate and setting either will change the other. they're literally linked, it's giving soulmate behavior 💜

uinterval

read-write, unsigned interval

Similar to the udate field, except corresponds to the interval value.

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⭐ STANDARD PROPERTIES ⭐

the everyday basics, the reliable besties 🌸

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.

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 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, don't build your whole app on her 💅

type

read-only, ascii

Part name assigned by Dallas Semi. E.g. DS2401 Alternative packaging (iButton vs chip) will not be distinguished.

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🚨 ALARMS 🚨

None implemented.

that's it. that's the whole section. not a single alarm, we love a low-drama chip 😌

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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. (power AND data on one wire? she's efficient, she's iconic ⚡)

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 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. (yes bestie, your hardware is literally a folder of files now, slay 🎀)

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. 🐢 > 🐇 fr fr

DS1427 DS1994 DS2404 DS2404S

The DS1427 (3), DS1994 (3), DS2404 (3), and DS2404S (3) family of 1-wire devices includes clock functions, with timers, memory, counters and alarms. It is possible to write-protect regions of memory. Uses include software or hardware timing and control.

Chips

Both the DS2404 (3) and DS2404S (3) have 1-wire and 3-wire interfaces, which might be useful for transferring data between the 2 buses. They act as a passive slave to both buses. The DS2404 (3) and DS2404S (3) require an external source of power and an external crystal. They also offer a reset and 1HZ clock pin.

iButtons

Both the DS1427 and DS1994 offer the memory, alarms, and clock function in iButton format. Because the iButton is a complete sealed package, battery and crystal are internal. Everything is access via the 1-wire interface. self-contained queen 👑

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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. (if it's wrong the whole thing is a no 💀)

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📄 DATASHEET 📄

http://pdfserv.maxim-ic.com/en/ds/DS2404.pdf
http://pdfserv.maxim-ic.com/en/ds/DS2404S-C01.pdf
http://pdfserv.maxim-ic.com/en/ds/DS1994.pdf
http://pdfserv.maxim-ic.com/en/ds/DS1427.pdf

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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)

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and that's the whole page bestie, you ate that 💅 the OWFS Manpage version dropped in 2006, and this is DS2404 (3) — go forth and clock some things 🕐✨