The Basler dart Camera Module – Soon Also Available for the MIPI CSI-2 Interface
This year Basler will offer the option to operate its dart camera modules via the CSI-2 camera interface of major embedded processing platforms. This creates the option to use the dart extension, a clever extension for dart camera modules with BCON interface.
The MIPI Alliance (www.mipi.org) specifies the CSI-2 (Camera Serial Interface 2) as a standard. The MIPI (Mobile Industry Processor Interface) Alliance is an organization of leading manufacturers of mobile or embedded applications and, with the CSI specifications, originally created a uniform interface for image sensors in smartphones or tablets.
Strengths and Weaknesses of the CSI-2 Interface
Since nearly all embedded processors are equipped with one or even several CSI-2 interfaces by now, CSI-2 essentially represents the standard interface for all types of embedded vision solutions. The advantages of this interface are:
- high available bandwidth (up to 2.5 Gbit/s per lane; depending on the bandwidth requirements, image data are typically transferred through 2 to 4 lanes)
- the option of an extremely lean setup; all required hardware is already available on the processor chip (SoC = system on chip), enabling direct processor communication without overhead.
However, CSI-2 can also pose practical difficulties, which explain why this interface has not had strong uptake as a standard for industrial applications so far.
- Since CSI-2 was primarily developed as an interface for smartphones, etc., little attention was given to larger cable lengths. That is why the maximum length between the sensor and CSI-2 connection is only 10 to 20 cm.
- Each combination of an image sensor with a certain SoC requires a specific driver, which may not yet exist for the selected setup and may first need to be developed.
dart Extension: CSI-2 with Industry-Friendly Extensions
With its dart extension, Basler will offer an industry-friendly approach to supplement the dart camera module with BCON interface, which utilizes the benefits of the CSI-2 interface while also offering a suitable solution for its particular aspects:
- An additional extension board with the size of a dart camera module – the dart extension – turns the BCON camera into a MIPI CSI-2 camera. By using a short flat flex cable, the extension board can be combined into a board stack with the dart camera module. Thanks to the BCON interface, the length of the flat flex cable can be one meter or more, which allows for much longer cable lengths than would otherwise be possible with a CSI-2.
- A generic driver ensures that all dart camera modules with BCON interface can be operated on all supported embedded platforms without first having to develop a separate driver. This basically makes the camera plug and play- with a CSI-2 connection.
- As an API the tried-and-tested pylon Camera Software Suite is available. The dart BCON thus continues to be a GenICam-compatible camera module and enables the full use of the camera’s entire set of features. Existing pylonbased (e.g. desktop) applications can be easily ported to an embedded target with CSI-2.
As well, the dart extension enables the use of a design-in-kit: The switch plan, PCB layout and other documents for the dart extension are provided in open source format. This also makes it possible to implement the conversion from BCON for LVDS to MIPI CSI-2 directly on the target host system and thus reduce the manufacturing costs.
dart Extension as Basler PowerPack
For those who want to start immediately, the dart extension as Basler PowerPack will be delivered with the dart camera module, lens, all required cables and the appropriate CSI-2 plugs for all supported embedded boards. The PowerPack contains everything for immediate camera operation. At the same time, the PowerPack is the reference implementation for a separate design-in.