'\"
'\" Copyright (c) 2003-2004 Paul H Alfille, MD
'\" (paul.alfille@gmail.com)
'\"
'\" Device manual page for the OWFS -- 1-wire filesystem package
'\" Based on Dallas Semiconductor, Inc's datasheets, and trial and error.
'\"
'\" Free for all use. No warranty. None. Use at your own risk.
'\" $Id$
'\"
.TH DS28E04-100 3  2003 "OWFS Manpage" "One-Wire File System"
.SH NAME
.B DS28E04
\- 1-Wire EEPROM chip (4096-bit) with seven address inputs
.SH SYNOPSIS
4096-bit EEPROM, 2 port switch
.PP
.B 1C
[.]XXXXXXXXXXXX[XX][/[
.B latch.[0-1|ALL|BYTE]
|
.B PIO.[0-1|ALL|BYTE]
|
.B power
|
.B sensed.[0-1|ALL|BYTE]
|
.B polarity
|
.B por
|
.B set_alarm
|
'\"
'\" Copyright (c) 2003-2004 Paul H Alfille, MD
'\" (paul.alfille@gmail.com)
'\"
'\" Program manual page for the OWFS -- 1-wire filesystem package
'\" Based on Dallas Semiconductor, Inc's datasheets, and trial and error.
'\"
'\" Free for all use. No warranty. None. Use at your own risk.
'\" $Id$
'\"
.B address
|
.B crc8
|
.B id
|
.B locator
|
.B r_address
|
.B r_id
|
.B r_locator
|
.B type
]]
.SH FAMILY CODE
.PP
.I 1C
.SH SPECIAL PROPERTIES
.SS latch.0 latch.1 latch.ALL latch.BYTE
.I read-write, binary
.br
The 2 pins (PIO) latch a bit when their state changes, either externally, or through a write to the pin. 
.br
Reading the
.I latch
property indicates that the latch has been set.
.br
Writing any data to ANY 
.I latch 
will reset them all. (This is the hardware design).
.br
.I ALL
is all 
.I latch 
states, accessed simultaneously, comma separated.
.br
.I BYTE
references all channels simultaneously as a single byte. Channel 0 is bit 0.
.SS PIO.0 PIO.1 PIO.ALL PIO.BYTE
.I read-write, yes-no
.br
State of the open-drain output (
.I PIO
) pin. 0 = non-conducting = off, 1 = conducting = on.
.br
Writing zero will turn off the switch, non-zero will turn on the switch. Reading the
.I PIO
state will return the switch setting. To determine the actual logic level at the switch, refer to the
.I sensed.0 sensed.1 sensed.ALL sensed.BYTE
property.
.br
.I ALL
references all channels simultaneously, comma separated.
.br
.I BYTE
references all channels simultaneously as a single byte. Channel 0 is bit 0.
.SS power
.I read-only, yes-no
.br
Is the
.I DS28E04
powered parasitically (=0) or separately on the Vcc pin (=1)?
.SS sensed.0 sensed.1 sensed.ALL sensed.BYTE
.I read-only, yes-no
.br
Logic level at the
.I PIO
pin. 0 = ground. 1 = high (~2.4V - 5V ). Really makes sense only if the
.I PIO
state is set to zero (off), else will read zero.
.br
.I ALL
references all channels simultaneously, comma separated.
.br
.I BYTE
references all channels simultaneously as a single byte. Channel 0 is bit 0.
.SS polarity
.I read-only, yes-no
.br
Reports the state of the POL pin. The state of the POL pin specifies whether the PIO pins P0
and P1 power up high or low. The polarity of a pulse generated at a PIO pin is the opposite
of the pin's power-up state.
.TP
.I 0
PIO powers up 0
.TP
.I 1
PIO powers up 1
.PP
.SS por
.I read-write, yes-no
.br
Specifies whether the device has performed power-on reset. This bit can only
be cleared to 0 under software control. As long as this bit is 1 the device
will always respond to a conditional search.
.SS set_alarm
.I read-write, integer unsigned (0-333)
.br
A number consisting of 3 digits XYY, where:
.TP
X
select source and logical term 
.br 
.I 0
PIO   OR 
.br 
.I 1
latch OR 
.br 
.I 2
PIO   AND 
.br 
.I 3
latch AND
.TP
Y
select channel and polarity
.br 
.I 0
Unselected (LOW) 
.br
.I 1
Unselected (HIGH) 
.br
.I 2
Selected    LOW 
.br
.I 3
Selected    HIGH
.PP
All digits will be truncated to the 0-3 range. Leading zeroes are optional. Low-order digit is channel 0.
.PP
Example:
.TP
133
Responds on Conditional Search when latch.1 or latch.0 are set to 1.
.TP
222
Responds on Conditional Search when sensed.1 and sensed.0 are set to 0.
.TP
000 (0)
Never responds to Conditional Search.
.SH STANDARD PROPERTIES
'\"
'\" Copyright (c) 2003-2004 Paul H Alfille, MD
'\" (paul.alfille@gmail.com)
'\"
'\" Program manual page for the OWFS -- 1-wire filesystem package
'\" Based on Dallas Semiconductor, Inc's datasheets, and trial and error.
'\"
'\" Free for all use. No warranty. None. Use at your own risk.
'\" $Id$
'\"
.SS address
.SS r_address
.I read-only, ascii
.br
The entire 64-bit unique ID. Given as upper case hexadecimal digits (0-9A-F).
.br
.I address
starts with the
.I family
code
.br
.I r address
is the
.I address
in reverse order, which is often used in other applications and labeling.
.SS crc8
.I read-only, ascii
.br
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).
.SS family
.I read-only, ascii
.br
The 8-bit family code. Unique to each
.I type
of device. Given as upper case hexadecimal digits (0-9A-F).
.SS id
.SS r_id
.I read-only, ascii
.br
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).
.br
.I r id
is the
.I id
in reverse order, which is often used in other applications and labeling.
.SS locator
.SS r_locator
.I read-only, ascii
.br
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
.B Link Locator
the
.I locator will show a unique 8-byte number (16 character hexadecimal) starting with family code FE.
.br
If no
.B Link Locator
is between the device and the master, the
.I locator
field will be all FF.
.br
.I r locator
is the
.I locator
in reverse order.
.SS present (DEPRECATED)
.I read-only, yes-no
.br
Is the device currently
.I present
on the 1-wire bus?
.SS type
.I read-only, ascii
.br
Part name assigned by Dallas Semi. E.g.
.I DS2401
Alternative packaging (iButton vs chip) will not be distiguished.
.SH ALARMS
Use the
.I set_alarm
property to set the alarm triggering criteria.
.SH DESCRIPTION
'\"
'\" Copyright (c) 2003-2004 Paul H Alfille, MD
'\" (paul.alfille@gmail.com)
'\"
'\" Program manual page for the OWFS -- 1-wire filesystem package
'\" Based on Dallas Semiconductor, Inc's datasheets, and trial and error.
'\"
'\" Free for all use. No warranty. None. Use at your own risk.
'\" $Id$
'\"
.SS 1-Wire
.I 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.
.PP
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.
.PP
The 1-wire scheme uses a single 
.I bus master
and multiple
.I slaves
on the same wire. The bus master initiates all communication. The slaves can be 
individually discovered and addressed using their unique ID.
.PP
Bus masters come in a variety of configurations including serial, parallel, i2c, network or USB
adapters.
.SS OWFS design
.I 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.
.PP 
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.
.SS DS28E04
The
.B DS28E04 (3)
is a memory chip that bends the unique addressing capabilities of the 
.I 1-wire
design. Some of the ID bits can be assigned by hardware.
.SH ADDRESSING
'\"
'\" Copyright (c) 2003-2004 Paul H Alfille, MD
'\" (paul.alfille@gmail.com)
'\"
'\" Program manual page for the OWFS -- 1-wire filesystem package
'\" Based on Dallas Semiconductor, Inc's datasheets, and trial and error.
'\"
'\" Free for all use. No warranty. None. Use at your own risk.
'\" $Id$
'\"
All 1-wire devices are factory assigned a unique 64-bit address. This address is of the form:
.TP
.B Family Code
8 bits
.TP
.B Address
48 bits
.TP
.B CRC
8 bits
.IP
.PP
Addressing under OWFS is in hexadecimal, of form:
.IP
.B 01.123456789ABC
.PP
where
.B 01
is an example 8-bit family code, and
.B 12345678ABC
is an example 48 bit address.
.PP
The dot is optional, and the CRC code can included. If included, it must be correct.
.SH DATASHEET
.br
http://pdfserv.maxim-ic.com/en/ds/DS28E04.pdf
.SH SEE ALSO
.SS Programs
.B owfs (1) owhttpd (1) owftpd (1) owserver (1)
.B owdir (1) owread (1) owwrite (1) owpresent (1)
.B owtap (1)
.SS Configuration and testing
.B owfs (5) owtap (1) owmon (1)
.SS Language bindings
.B owtcl (3) owperl (3) owcapi (3)
.SS Clocks
.B DS1427 (3) DS1904 (3) DS1994 (3) DS2404 (3) DS2404S (3) DS2415 (3) DS2417 (3)
.SS ID
.B DS2401 (3) DS2411 (3) DS1990A (3)
.SS Memory
.B 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)
.SS Switches
.B DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3)
.SS Temperature
.B 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)
.SS Humidity
.B DS1922 (3) DS2438 (3) EDS0065 (3) EDS0068 (3)
.SS Voltage
.B DS2450 (3)
.SS Resistance
.B DS2890 (3)
.SS Multifunction (current, voltage, temperature)
.B DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3) DS2756 (3) DS2760 (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)
.SS Counter
.B DS2423 (3)
.SS LCD Screen
.B LCD (3) DS2408 (3)
.SS Crypto
.B DS1977 (3)
.SS Pressure
.B DS2406 (3) TAI8570 (3) EDS0066 (3) EDS0068 (3)
.SS Moisture
.B EEEF (3) DS2438 (3)
.SH AVAILABILITY
http://www.owfs.org
.SH AUTHOR
Paul Alfille (paul.alfille@gmail.com)