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On the left of the Raspberry logo, there is a DSI connector. I am not familiar with this standard. What sort of displays can I connect to using this connector? And can I buy these displays off the shelf?

Also are there any consumer device that we could scavenge a display from that would work with the Pi? Mobiles? Game Consoles? Kitchen implements? :)

ACarter
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Maria Zverina
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  • There is a tiny bit of info here: http://en.wikipedia.org/wiki/Display_Serial_Interface. – Maria Zverina Jun 19 '12 at 16:01
  • DSI hmm... I have some DSI displays and yes, you can scavenge some stuff. I bought a old broken DS and scavenged the display and I could use the pi as a portacomputer so , I guess this is quite a bit of news. –  Nov 25 '13 at 00:43

3 Answers3

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The Raspberry Pi foundation has announced that The official Raspberry Pi touchscreen display is now available. This is a ten-point touchscreen, which connects to the DSI connector and has full kernel support, after an upgrade.

Given that this has taken the foundation several years to finish, I doubt it is something that anyone could easily hack together from spare parts.

Background

The Wikipedia Display Serial Interface page says:

The Display Serial Interface (DSI) is a specification by the Mobile Industry Processor Interface (MIPI) Alliance aimed at reducing the cost of display sub-systems in a mobile device. It is commonly targeted at LCD and similar display technologies. It defines a serial bus and a communication protocol between the host (source of the image data) and the device (destination of the image data).

At the physical layer, DSI specifies a high-speed differential signaling point-to-point serial bus. This bus includes one high speed clock lane and one or more data lanes. Each lane is carried on two wires (due to differential signaling). All lanes travel from the DSI host to the DSI device, except for the first data lane (lane 0), which is capable of a bus turnaround (BTA) operation that allows it to reverse transmission direction.

According to this forum thread DSI screens will need new GPU drivers to enable DSI output:

if you manage to use the dsi connector (i.e. kidnap some bc engineer and let him produce a new gpu-binary for your dsi-connected screen) you could in fact have a working dual display setup...

As such, although official DSI screens are now available, and there is kernel support, it is unlikely that that such support would extend to arbitrary other implementations of DSI screens. Given what the wikipedia page says about the protocol, DSI is hardly a smart way of doing things these days (the protocol is complicated by the need to support displays without on-board memory) and it is possible that any given GPU binary may only work with a limited set of specifically supported devices, rather than supporting any arbitrary DSI display.

Community
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Mark Booth
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  • Hmmm .. not sure about this. The standard dates back to 2004 and is specifically aimed at mobile devices. Makes the use of CRT display somewhat doubtful - no? And given that it's supported by most of the big names in mobile, surely there have to be DSI screens out there today. Can we perhaps even scavenge suitable BC gpu blob from one of these devices? – Maria Zverina Jun 19 '12 at 17:36
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    @Maria, no what I mean is that the protocol still mentions blanking period etc. which were only needed in the days of CRT's, to give the electron beam time to get back to the start of the next row or top of the screen. Anything to do with the GPU is effectively going to need the Raspberry Pi Foundation to do the work, since the GPU software is closed source. – Mark Booth Jun 19 '12 at 17:42
  • I think there is a touch screen coming, so that would totally work with the IO of the DSI – Hellonearthis Aug 09 '12 at 19:16
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    DSI is hardly a smart way of doing things these days (the protocol is mired in the days of CRT fly-back blanking periods) You can hardly be more wrong.. DSI is the standard at the moment and will remain that way for some time. You are also wrong about the blankings. Whenever you have a display driver without RAM, then you need to use the DSI videomode which includes blankings. If you have a display driver including RAM then you can switch over to DSI command mode which does not need blankings... I am assuming the ribbon cable is a standard DSI interface cable. There is no standard cable –  Jul 07 '13 at 08:42
  • I've updated my answer @Erwin, with regard to blanking periods, I still don't think that DSI is a smart way to provide a Raspberry Pi display though, it's just too difficult to integrate. – Mark Booth Jul 09 '13 at 10:44
  • How can we use this. Can we directly connect to screen using this? http://in.element14.com/raspberry-pi/rpi-cmdk-adapter/adapter-compute-module-camera/dp/2433318?MER=MER-L52-L5IB-PD-ACC-DBE – nbsrujan Aug 12 '15 at 13:08
  • Sorry @nbsrujan , that adapter only allows you to use a DSI screen made for the Raspberry Pi with a Raspberry Pi compute/IO board. Sadly, since there are no Raspberry Pi display modules yet, there isn't anything which will work with the adapter. – Mark Booth Aug 12 '15 at 16:58
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From Using cell phone screens with any HDMI interface, there is a video controller, made from an Arduino DSI Display Shield with a programmable FPGA (Xilinx Spartan-6-SLX9), that bridges the iPhone4 display interface to DSI interface.

HDMI to DSI interface

Greenonline
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user110251
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The Nintendo DS uses a touch screen DSI display, but so far that is the only consumer device I have seen that you can get replacement screens to be fitted to the Raspberry Pi. I have no idea what compatibility issues you might run into if there are any proprietary measures taken though, and I am assuming the ribbon cable is a standard DSI interface cable.

Adrien
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