- MambaNet
-
MambaNet is a protocol designed to have hardware controller controlling a virtual device (e.g. computer applications/processes). The developers of MambaNet have seen that equipment developed with the last available technologies become more and more complex to control. Often there is a lot of (virtual) functionality available. You can access this functionality by a screen, keyboard and mouse. But some applications required dedicated and direct control via hardware and/or (embedded) software from remote locations. This is for example a requirement in the 'live' audio industry (Radio/TV broadcasting studios), where a lot of audio-storage and processing takes place in 'computers' (e.g. virtual mixing/play out).
Because the protocol is very new its not yet widespread, but there is a high potential. Current implementations are done by Broadcast Partners[1] and D&R [2]
The functionality which is required, is not delivered by a single company. Often you can select a range of products/brands. In practice this brings a question: 'How will all my equipment work together?'
The radio studio example shows that in the past, and also in current implementations, the pieces of audio equipment are connected through remotes (also called GPIO). In fact, these are TTL or Relais inputs and outputs, where you have a hardwired connection between products.
With the raising amount of functionality its complex make profit of all the functionality in your devices, using the same 'control interface'. This is the point where MambaNet could be very interesting.
Contents
Definitions
- Node
A unique identified software process or PCB/hardware. For modularity its possible to have multiple nodes in a physical device. The node can send and receive data with this object.
- Object
This represents an element that can be set or triggered by a user. To trigger an object (think of pushing a button), you can implement a sensor part. To set an object (think of setting a LED/Display), you can implement an actuator part.
- Sensor
A sensor waits for a user action or timeout and sends its information to the network if desired.
- Actuator
A actuator receives information from the network, which may set a LED or fader etc.
- Engine
An engine is a special node type. This type of node is allowed to process sensor changes and to sent actuator changes. In fact the engine is the part that gives manufacture specific functionality to a device. For example the radio studio mixing console has one engine, the virtual mixing console. But is has multiple nodes that control the engine, this can be the control surface or any software application.
Specifications
- Multi master
Most available control protocols (e.g. SNMP) are based on the client-server principle. For MambaNet it is important that its works multi-master, so a controller at a 'button surface' can immediately contact its functional counterpart.
- Medium and Transport Layer independent
It is required to protocol can run from 8 bits micro controllers till advanced machines, which means that the physical connections that have to run MambaNet can be different as well. Currently MambaNet is implemented over RS232, CAN, Ethernet and TCP/IP.
- Object oriented design
To simplify to way of thinking, the protocol has an object oriented design. That means you are allowed to design your own node with objects and share in a MambaNet network. Even there is a registration method for the objects, which is required to implement in a node. With this information the protocol will be future proof and its easy use MambaNet enabled products from other manufacturers (Without knowing the device).
- Open for all manufactures to use
The protocol is developed by D&R Electronica Weesp B.V. they maintain a list of manufacture IDs (The protocol allows 65534 manufactures to get their own ID). For local development one ID is left free, this means end-users can also make their own MambaNet complaint software/hardware. (In the radio studio example this can be very interesting for local and regional broadcast facilities). With the reservation of a Manufacture ID a range of 4294836225 Unique numbers is available for this single manufacturer.
- On a node you can have up to 64k custom objects. The limit is determined by the footprint in your controller/application.
- Although to protocol is designed for tiny controllers its still possible to have relative large messages (for an embedded system). You can send up to 98 bytes per single MambaNet message.
- Auto learning of nodes.
Each node contains a list of all available objects. This list gives a description and data type/ranges an object works with. All this information makes it possible for engines to 'discover' a device and make use of its objects. Practical this means the engines are future proof and can use equipment from manufacturers they even do not know about.
Data formats
There are some primitive data types that can be used in MambaNet:
- No data
A part of an object is not implemented (e.g. an LED only has an actuator part)
- Unsigned integer
Can be a position or speed.
- Signed integer
Think of a controller if an offset variable (e.g. an encoder)
- State
For example, to select a samplerate you can have 2 states: 44.1 kHz and 48 kHz
- Octet string
Is an array of bytes which can be used to set a text string on a display.
- Float
Makes it possible to set values in the float format (e.g. temperature or dB level).
- Bit string
Useful if you want to set several bits (e.g. status bits or LED bar).
- Object information
The datatype that contains all information to learn objects of a node.
- Error
This indicates an error occurred; the text string gives information in 'ASCII'.
Compatibility
MambaNet will run over various physical and transport layers. Currently we have focused on CAN and Ethernet.
- CAN
On the CAN network MambaNet can no coexist with other protocols, this because the addressing scheme makes advanced use of the CAN identifiers.
- Ethernet
MambaNet over Ethernet will adapt the level 2 Ethernet standard (communication by MAC address). This means MambaNet can run over standard Ethernet networks (e.g. your data network). It will be possible to run MambaNet in parallel with any other Ethernet protocol that runs on Ethernet level 2. For example its no problem to run MambaNet in combination with Audio over Ethernet protocols like CobraNet or a higher level protocol like LiveWire[3](based on RTSP) can be a good combination. Of course you always have to care there is enough bandwidth on your network to do all tasks you require!
References
External links
Categories:- Audio engineering
- Network protocols
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