DS2436 - Man Page
Battery ID/Monitor Chip
Synopsis
Temperature Voltage and Memory.
1B [.]XXXXXXXXXXXX[XX][/[ pages/page.[0-4|ALL] | temperature | volts | counter/cycles | counter/reset | counter/increment | address | crc8 | id | locator | r_address | r_id | r_locator | type ]]
Family Code
1B
Special Properties
pages/page.0 ... pages/page.4 pages/page.ALL
read-write, binary
Memory is split into 5 pages of 32 bytes each. Only the first 3 pages are really available, and some of that appears to be reserved. See the datasheet for details.
pages/page.0 is locked and unlocked transparently for every write.
ALL is an aggregate of the pages. Each page is accessed sequentially.
temperature
read-only, floating point
Temperature read by the chip at high resolution (~13 bits). Units are selected from the invoking command line. See owfs(1) or owhttpd(1) for choices. Default is Celsius. Conversion takes ~20 msec.
volts
read-only, floating point
Voltage read (~10 bits) at the chip's supply voltage Vdd. Range 2.4V to 10V.
counter/
A resettable non-volatile counter intended for counting battery discharge cycles.
counter/cycles
read-only, unsigned integer
Cycle counter value. Stored at memory location 0x82.
counter/increment
write-only, yes/no
Any non-zero (true) value will increment counter/cycles by one.
counter/reset
write-only, yes/no
Any non-zero (true) value will reset counter/cycles to zero.
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.
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.
DS2436
The DS2436 (3) is a simpler form of the DS2438 battery chip. It has no counter, and only one voltage sensor.
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
See Also
Programs
owfs (1) owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1) owwrite (1) owpresent (1) owtap (1)
Configuration and testing
Language bindings
owtcl (3) owperl (3) owcapi (3)
Clocks
DS1427 (3) DS1904 (3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3) DS2417 (3)
Id
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
Resistance
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
LCD Screen
Crypto
Pressure
DS2406 (3) TAI8570 (3) EDS0066 (3) EDS0068 (3)
Moisture
Availability
Author
Paul Alfille (paul.alfille@gmail.com)
Referenced By
DS1821(3), DS1822(3), DS1825(3), DS18B20(3), DS18S20(3), DS1921(3), DS1963L(3), DS1963S(3), DS1977(3), DS1991(3), DS1992(3), DS1993(3), DS1995(3), DS1996(3), DS2401(3), DS2404(3), DS2405(3), DS2406(3), DS2408(3), DS2409(3), DS2413(3), DS2415(3), DS2423(3), DS2430A(3), DS2431(3), DS2433(3), DS2437(3), DS2438(3), DS2450(3), DS2502(3), DS2505(3), DS2506(3), DS2720(3), DS2740(3), DS2751(3), DS2755(3), DS2760(3), DS2770(3), DS2780(3), DS2781(3), DS2890(3), DS28E04(3), DS28EA00(3), DS28EC20(3), EDS(3), EEEF(3), IBLSS(3), InfernoEmbedded(3), LCD(3), mAM001(3), mCM001(3), mDI001(3), mRS001(3), owcapi(1), owfs(1), owfs(5), owftpd(1), owhttpd(1), owmon(1), ownet(1), owperl(3), owserver(1), owshell(1), owtap(1), owtcl(n).