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Welcome to BiDiB.org

What means BiDiB?

BiDiB® is short for BiDirectional Bus and it's becoming the standard bus for computer based model railway control. The name BiDiB stands for the protocol itself and this can be implemented in many different physical connections like Ethernet, USB or BiDiBus which is designed especially for the needs of huge layouts.

Why do we need a new bus system?

  • In connection with railcom enabled feedback systems there is a gap in the available bus protocols as they don't have enough bandwidth and/or they are closed source which makes it impossible to send BiDi data. BiDiB opens up new opportunities – as example when registering a new loco on the track (Image Transfer) and during operation (transfer of the actual speed). All of this technologies have high demand for bandwidth and BidiB can do the job.
  • Existing bus systems for model railways have some deficits like non-protected transmission, fault prone, and are difficult in configuration (address allocation) which results in high support requirements.
  • Existing bus systems are stand alone solutions and remain incomplete as there are feedback bus, booster bus, handheld controller bus and so on. BiDiB fit's all of this into one bus!
  • Existing bus systems are limited in their wiring topology. This causes problems in huge layouts and specially layouts in U or L shape are affected.

What are the objectives of BiDiB and what is it based on?

First of all in the BiDiB design process there is the definition of the requirements and design specification according to the planned use:

  • Model railways are often centrally operated, but interaction between user and control unit is often decentralized. The central control knows the logical structure of a system and guarantees the operation (e.g. unique assignment to handheld units) and the security (e.g. track monitoring). The bus system must support this effectively.
  • The logical structure of the layout may fall in substructures (module systems). Nothing needs to be reconfigured at modifications or ad-hoc meetings.
  • The bus system must be safe in operation, the electrically design has to be stable and also a perfect logical security of the bus is required.
  • The system must be able to provide software updates of components via bus system. Disassembling or further settings or modifications at the bus location is not necessary.
  • The bus system must be easy in operation. This means in detail: Easy wiring, automatic establishing of a connection and simple configuration.
  • Components of the bus system must be compatible between different vendors.
  • The bus system must be able to work with different physical implementations (e.g. USB, Ethernet, wireless).

What are the advantages of BiDiB?

  • BiDiB is an future proof open standard for all vendors.
  • BiDiB is fast: Features of modern microcontrollers will be used, no slow reaction on huge layouts any more.
  • BiDiB is plug&play: Addressing is similar to USB – just plug it in and you are done.
  • BiDiB is easy: Identification mode for simple locating of units within the bus system.
  • BiDiB is user friendly: modules are accessed with their name, you can add personal text like "detectors main station". This text is stored inside the modules and can be used in all programs
  • BiDiB is expandable: the protocol allows for hubs to run large layouts with difficult wiring topologies. Node assignments are retained even in a case of conversion.
  • BiDiB is available for many different signal transmission technologies – even wireless.
  • BiDiB is safe: Lost transmission packets will be detected and automatically repeated. Failed nodes will be recognized and reported. Turnout positions will be reported too.
  • BiDiB is maintainable: Nodes can be updated with new firmware/software without while remaining in place on the bus. There are no programmers nor special software necessary.
  • BiDiB ensures layout operation: if a locomotive gets lost (derailment, loose connection) the hosts get a message.
  • BiDiB brings up new features: e.g. Occupancy detectors can recognize multiple locos in one section, light controls running on their own processes and booster assemblies can transmit present condition and current power consumption.
  • BiDiB fully supports RailComPlus®.
  • BiDiB fully supports automatic decoder logon via DCCA.

Does your bus system have these as well?