 The HA7Net is a low-cost Ethernet to 1-Wire interface designed
to simplify the process of integrating distributed 1-Wire / iButton networks into
your application or system. The HA7Net allows end users to enjoy easy
remote access to their 1-Wire sensors and devices. Likewise, integrators and OEMs can substantially
decrease development time and installation costs associated with
deploying systems based on Dallas Semiconductor 1-Wire technologies.
High-Level Device Support
The HA7Net supports a variety of 1-Wire devices at a high level. For
example, reading the current temperature from a DS18S20 doesn't require the user
to learn the details of reading and parsing scratchpads. Instead, you
simply ask the HA7Net for the current temperature and it handles all of the
required low-level communications for you, as shown in the following example:
Here you can see that the HA7Net was asked to read the current temperature from
a DS18S20, a DS18B20, and a DS2438. The HA7Net sequentially read and
parsed the data from each of the devices, and returned a single HTML page
showing the current temperature and operating resolution for each sensor.
1-Wire devices that are currently supported at a high-level include:
- BAR2001S : Pressure Sensor
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- DS18B20 : Temperature Sensor
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- DS18S20 : Temperature Sensor
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- DS1920 : Temperature iButton
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- DS2438 (Temperature Only)
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- DSP7X4 Display : Large Display
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- GP1 Counter : General Purpose Counter
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- HMP2001S : Humidity / Temp Sensor
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- HTP-20 Humidity / Temp Sensor
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- T8A 0-5 V 8 Channel Analog Input
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- AAG TAI8520 Temperature Sensor
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- AAG TAI8540D Humidity Module
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- AAG TAI8586 Counter Module
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We continually work to add high-level support for additional 1-Wire devices,
and we periodically make firmware upgrades available for download on our
technical support website. To view the latest firmware news, or to
download the latest firmware, please see the following knowledgebase article:
HA7Net Firmware Download
Low-Level 1-Wire Support
The HA7Net provides a robust low-level command set supporting operations
ranging from reading CRC validated TMEX UDP records to wiggling the 1-Wire bus
on and off 1 bit at a time. This means that you can talk to any 1-Wire
device manufactured by Dallas Semiconductor, whether the HA7Net provides
high-level support for that particular device or not. For a complete
discussion of the low-level command set, please refer to the
HA7Net Users Manual.
Field Upgradeable
The HA7Net features remotely upgradeable firmware. We periodically release
updated firmware with additional features that you may want to install onto your
HA7Net. If you can access your HA7Net via the network, then you can
upgrade its firmware without having to physically visit it or uninstall it from
its deployed location.
Communication Protocols
Primary communication with the HA7Net is accomplished via the HTTP protocol,
with optional 128 bit SSL data encryption. The actual data is exchanged in
the form of html documents which have been designed to accommodate both human readability
and 100% reliable machine parsing. This is accomplished through the use of unique,
predictably named form fields that can be automatically parsed by most DOM parsers,
or easily digested via regular expressions on lighter weight platforms. Data is
passed to the HA7Net in the form of parameters placed in the URL. Since the result
pages are human readable, both proof of concept and integration times are reduced
as you can effectively interact with 1-Wire devices via the HA7Net using a standard
web browser.
The HA7Net will allow you to use industry standard Ethernet products (switches,
hubs, etc.) to build out the backbone of your 1-Wire based sensor / control system.
This provides several important benefits: First, 1-Wire networks can be easily
distributed over great distances without having to deal with the challenges associated
with the installation of physically large 1-Wire networks. By designing
your sensor networks in a distributed star topology, the individual 1-Wire MicroLans can be kept to a smaller physical
size, thereby improving reliability and decreasing installation costs. Second,
since the HA7Net communicates via TCP/IP over standard Ethernet, you can take advantage
of existing corporate LANs, the Internet, and in-house MIS expertise for building
out and maintaining the backbone of your sensor network. Another advantage
is the number of readily available libraries and developer tools which are widely
available for common platforms, and can be used to communicate with the HA7Net.
Additionally, a complete debugging / logging facility is provided via a built-in
telnet server. A multicast listener has also been integrated to provide ease
of discovery in dynamically configured networks..
Other
The HA7Net can perform Search and Family search functions making it easy to acquire
the unique 64 bit serial numbers of all connected devices. Many sensor devices require
that extra power be delivered during periods of data conversions (DS1920 and DS1820
temperature sensors for example). The HA7Net automatically provides the extra current
these devices require with a built in smart strong-pull-up. Dallas Semiconductor
iButtons which store data in TMEX Touch Memory File format can be read or written
with simple commands. The HA7Net will automatically generate and check the CRC16
error checks from Touch Memory File records. For a complete list of the 1-Wire
commands supported, please refer to the API reference in the
HA7Net user's manual.
Features
- Simple command support for all 1-Wire devices.
- Configurable security levels: Secure 128 bit SSL Encryption.
- Firmware can be flash upgraded from remote.
- Manages concurrent client connections safely and reliably.
- Debugging functionality helps simplify software integration.
- Integrated Real-Time Clock, with option to set periodically from a SNTP
server.
- 3 convenient 1-Wire ports with independently configurable Vcc settings.
- Automatically provides smart strong-pull-up for 1-Wire sensors.
- 1-Wire MicroLan capacity of 2000 feet of cable, 100 devices.
- Built-in Search, Family Search, and Conditional Search, and much more.
- ESD Protection more than 27kV (IEC801-2 Reference Model.) on the 1-Wire
bus.
- Block mode commands support all 1-Wire device functions.
- Automatic CRC16 for TMEX files.
- ABS enclosure. Available in either Panel mount or DIN-Rail mount versions.
- LED indicators for Ethernet link/activity, power, and 1-Wire activity.
- Low Cost.
Specifications
- Communication: 10/100 Ethernet via 8-Wire RJ-45 (ISO-8877). Both
half and full duplex modes of operation are supported.
- Network Protocols: HTTP, HTTPS, Telnet, Multicast, DHCP, SNTP
- Concurrent Connections: Supports 6 simultaneous http/s connections.
- Supply Voltage: 6-12 Volts Supply Current: 300 mA
- 1-Wire Devices: 100 devices
iButton and 1-Wire are registered trademarks of Dallas Semiconductor Corporation.
TMEX is a trademark of Dallas Semiconductor Corporation. |
