Motivation
The traditional ETS data model is not effective for devices containing many copies of essentially the same structure, and for configurable structures. Such data occurs often for devices with many channels (e.g. Gateways) or for highly configurable devices (e.g. sensors with touch display).
The problem here is that all possible data has to be explicitly included in the project data which has the following drawbacks:
- Unnecessarily large Application Programs (with long import and loading times and high resource consumption – even out-of-memory exceptions – in ETS)
- Risk of bugs introduced when manually copying the data in MT.
- Waste of device resources (e.g. in the object table) because each channel (or similar structure) has to accommodate for the maximum size of the contained data.
- This article presents suggestions to improve the ETS data model to take advantage of regularly structured Application Programs by a more modular approach.
This has the further advantage that it is easier to build new Application Programs from already available, tested and maybe translated building blocks.
Most of these topics have direct effect on product costs and quality.
Examples
Universal Touch Display with memory- mapped parameters
Consider a touch display which is capable of displaying up to 100 controls, each of which is either an OnOff function, a dimming function, or a shutter function.
The OnOff function is a realization of the FB 'Light Switching Sensor Basic' with two Group Objects (SwitchOnOff and InfoOnOff) and a few parameters. One of the parameters is the label to be displayed on the button in the UI.
The dimming function is a realization of the FB 'Dimming Sensor Basic' with three Group Objects (SwitchOnOff, InfoOnOff, Relative Setvalue Control) and a few parameters. One of the parameters is the label to be displayed on the button in the UI.
The shutter function is a realization of the FB 'Shutters and Blinds Sunblind Sensor Basic' with two Group Objects (Move Up Down and StopStep Up Down) and a few parameters. One of the parameters is the label to be displayed on the button in the UI.
Gateway
With the help of a DCA or a Button handler script, the number and type of devices connected to a gateway is determined. For each discovered device, a Module is instantiated: for devices of Type 1 Module type 1 and so on.
Manufacturer Tool & Demo
This video is a demo for MT in general.
This downloads contain a MAP specific demo, it includes a MT (v5.7.2) project and a dedicated KNX Virtual version.
The MT project contains 3 application programs with the exact same functionality, exact same memory layout and the exact same ETS parameter dialog for a dimmer with Application Number 0201h:
- Application Version 01h: this a 'regular' application program, i.e. it does not use any module
- Application Version 02h: this a modular application program, i.e. it contains 8 manually created instances of a module
- Application Version 03h: this modular application program uses the same module as in version 02h, but the 8 instances are created via 1 repeat and 3 allocator elements
The dimmer can be tested via an ETS Test Project in combination with the dedicated KNX Virtual version.