{"id":108,"date":"2017-07-23T17:02:55","date_gmt":"2017-07-23T17:02:55","guid":{"rendered":"http:\/\/endrekatona.eu\/wordpress\/?p=108"},"modified":"2017-08-31T20:05:39","modified_gmt":"2017-08-31T20:05:39","slug":"building-automation-with-knx-and-bims","status":"publish","type":"post","link":"http:\/\/endrekatona.eu\/tech\/2017\/07\/23\/building-automation-with-knx-and-bims\/","title":{"rendered":"Building automation with KNX and BIMs"},"content":{"rendered":"
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Developing and building smart homes have become trendy and cool in the last decades, as problems like energy efficiency and aging society were considered more and more serious.<\/p>\n

Different standards have been defined in order to create a basis for the building automation industry. A widely spread one is called KNX (Konnex).<\/p>\n<\/div>\n

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“KNX<\/b>\u00a0is a standardized\u00a0(EN 50090,\u00a0ISO\/IEC 14543),\u00a0OSI-based\u00a0network communications protocol\u00a0for\u00a0intelligent buildings. KNX is the successor to, and convergence of, three previous standards: the\u00a0European Home Systems Protocol\u00a0(EHS),\u00a0BatiBUS, and the\u00a0European Installation Bus\u00a0(EIB or\u00a0Instabus).<\/em><\/p>\n

The standard is based on the communication stack\u00a0of EIB but enlarged with the physical layers, configuration modes and application experience of BatiBUS and EHS.<\/em><\/p>\n

KNX is designed to be independent of any particular hardware platform. A KNX Device Network can be controlled by anything from an 8-bit microcontroller\u00a0to a PC, according to the needs of a particular implementation. The most common form of installation is over twisted pair medium.”\u00a0<\/em>(Wikipedia)<\/p>\n<\/div>\n

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The nice thing is, that a new appliance may be developed from scratch, and integrated into an already functional KNX-based smart building. No need to buy certain products\/technologies from specified companies, the newly developed system only needs to be able to communicate with other devices via the KNX bus. It does not matter which microcontroller is used for the development, though, the developer must implement a communication layer which conforms to the\u00a0KNX-standard.<\/p>\n<\/div>\n

\"\"<\/a>There is also another possibility, namely using BIMs: KNX B<\/strong>us <\/span>I<\/strong>nterface M<\/strong>odules. \u00a0These “bus interface modules are printed circuit boards consisting of the chipsets (TP-UART + KNX microcontroller) mounted with all necessary components”<\/em>. The BIM modules “contain the BCU 2.5 system software compliant to the KNX specification.”<\/em>\u00a0(Siemens Building Technologies)<\/a><\/div>\n

\n<\/i>I’ve googled a bit around, but I did not find any other BIM providers but Siemens.<\/span><\/span><\/span>The newest bus interface modules family developed by Siemens Building Technologies is called BIM M13x, and has 4 family members: M130, M131, M132, M135. (Actually, the only difference between M130 and M135 is that M135 may be used at extended temperature ranges.)<\/div>\n
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“The BIM M13x series is based on the NEC78K0\/Kx2 microcontroller family providing state of the art flash technology”.<\/span><\/em>\u00a0The family members basically differ from each other in the available Flash and RAM memory sizes that can be used by the application program. (Refer to the\u00a0Siemens webpage<\/a>\u00a0for the exact specifications)<\/p>\n<\/div>\n

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If the BIM modules are used to develop new KNX-appliances, the system developer can invest more time in creating the application specific hardware and software. He does not need to take care about the communication layer, as the communication with other KNX-devices can be easily implemented using the API, which calls the functions of the already installed firmware. (BCU 2.5)<\/p>\n

As it is observable from the picture, the pins of the KNX-microcontroller are wired to a socket, so that the application specific hardware can be easily connected. The application program can be downloaded to the BIM, by connecting it to the KNX-bus, and using the BIM-Tools for program download.<\/p>\n<\/div>\n

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Available development toolpackage<\/h3>\n
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The company\u00a0Opternus GmbH<\/a>\u00a0offers not only the BIM M13x modules, but also a “a modern\u00a0tool chain<\/a>\u00a0including debug tools leading to shorter development times.<\/span>“<\/em><\/p>\n

This toolpackage includes following items:<\/p>\n<\/div>\n

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