--- name: "DS2404" section: "3" platform: "linux" package: "owfs-doc" version: "3.2p4+dfsg1-6" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/DS2404" --- # DS2404(3) EconoRAM time chip ## NAME **DS2404** - EconoRAM time chip - **DS2404S** \- Dual port memory plus time - **DS1994** \- 4k plus time iButton - **DS1427** \- Time iButton ## SYNOPSIS Real time clock, 4kbit memory. 3-wire interface, too. **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** ## FAMILY CODE - *04* DS2404 DS1994 - *84* DS1427 DS2404S ## SPECIAL PROPERTIES ### 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.\ 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. ### date *read-write, ascii*\ 26 character date representation of the *udate* value. Increments once per second while *running*\ Actual internal representation has higher precision.\ 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. ### 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. - *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. ### uinterval *read-write, unsigned interval*\ Similar to the *udate* field, except corresponds to the *interval* value. ## 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. ### 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? ### type *read-only, ascii*\ Part name assigned by Dallas Semi. E.g. *DS2401* Alternative packaging (iButton vs chip) will not be distiguished. ## ALARMS None implemented. ## 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 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. 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. ### 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 regians 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. ## 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. ## 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 ## 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)