Up close with the Banana Pi
Camera and Display Modules
As I mentioned already, the Banana Pi camera board connector is not compatible with the Raspberry Pi camera module – it is physically larger and a different pitch, and it uses a different interface method. These differences are apparently due to the fact that the Allwinner A20 processor in the Banana Pi does not support the same MIPI CSI interface used by the Raspberry Pi camera but instead requires a parallel camera interface. A quick look at the specification of the Omnivision OV5647, which is the CMOS image sensor used in the Raspberry Pi camera module, revealed that the it is capable of using a parallel interface as well as the high-speed MIPI CSI interface.
At this moment, I could find no camera module available to purchase for the Banana Pi, but after digging around on some of the related websites, I discovered that a camera module based on the Omnivision OV5640 (Figure 5) is in the works. The OV5640 sensor [15] appears to be almost identical to the OV5647 [16] used in the Raspberry Pi, apart from the addition of embedded JPEG compression, a number of built-in image quality controls, and support for a variety of different output formats. (Bear in mind that I am by no means an expert on these sensors; this information is simply what I have found from the relevant datasheets, which may be incomplete).
You will find an LVDS display interface connector on the Banana Pi board, but like the camera interface, the LVDS display connector is not well documented. After trawling the LeMaker Banana Pi forums, I found a few posts from forum moderators (who also appear to be Banana Pi tech support), suggesting that a touch screen external display module is in the development and testing stage [17]. As with the camera modules, the display modules for the Banana and Raspberry Pis are not compatible with each other because of the different connection interface and physically different connector size.
Add-Ons and Accessories
As I mentioned previously, the 26-pin GPIO connector is supposedly pin compatible with the same header found on the Raspberry Pi, which means that your existing add-on boards should, at least from an electronic point of view, work with the Banana Pi.
The problem is that the RCA connector on the Banana Pi is closer to the GPIO header, and due to the mounting hole found in the corner of the board next to the GPIO header, the Banana Pi has shifted the header itself over a bit. This means it is also closer to the 3.5mm audio jack, USB, and Ethernet ports. In Figure 6, I have tried to connect a PiFace Digital add-on board to the Banana Pi. As you can see, it is not possible to fully connect to the GPIO header due to other components (specifically the RCA video and USB connectors) getting in the way.
Furthermore, any add-on boards that require the use of the Raspberry Pi mounting holes for support beams will not work either, because the mounting holes on the Banana Pi are in completely different places. This problem is not necessarily a deal breaker, but it is a bit frustrating.
Some add-on boards and accessories are available specifically for the Banana Pi, such as a case, an UNO extend board, a Banana Pi GPIO extend board (which is similar to an Adafruit T-Cobbler for the Raspberry Pi), and a Banana-Pi-compatible CSI/DSI cable. You'll find these products on one of the many Banana Pi websites [18], and some are also available from Ali Express [19]. I also suspect that more Banana Pi add-on boards and accessories will become available as time progresses.
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