Using the DSI connector on RasPi Zero W

Question

I'm search for compatible 4-6" touchscreens with the Raspberry Pi (Zero W, but I think it's the same for all of them) with capacitive digitizer. My questions are:

1. Does DSI support the touch digitizer or I'll have to buy/connect it externally?
2. What I have to look for in a datasheet to see if a screen is compatible? (for example is Nexus 5 screen/digitizer compatible?)

Just to be clear: I want to connect a screen DIRECTLY to the DSI. Not with a "daughter board" that breaks out HDMI.

If you have any recommendations for a (touch) screen please add them to the comments, but that's not the main question.

Answer 1

The Pi Zero W only has CSI for connecting to a camera module, but it hasn't a separate DSI for connecting a display. The DSI connector is only present on the A/Bs (and CM, if I'm not mistaken). The GPIO header only optionally carries DPI (used, for example, by the HyperPixel display).

Answer 2

Is use of DSI a must ?

As @TheDiveO says, the Pi Zero hasn't a separate DSI for connecting a display.

BUT, there are 7" touch screens with HDMI input available on Amazon US for $77 (that's the first one I found, but WaveShare have a great rep for displays).

The same display costs GBP £74 on Amazon UK This is a rip-off, as usual for the UK, using a 1:1 exchange rate. However, there are good alternatives for £45 (non-touch ) and for £53 (touch screen).

You can find similar, cheaper on Ali Express.

I would recommend buying a mini to standard HDMI cable, rather than using a converter with a standard cable.

Answer 3

You can use the DPI on the 20x2 pin header, but if you turn on that overlay

you basically loose all the other pin functionality (no i2c no SPI) this also means no touch, unless in some way your display can provide that infos via USB, anyway doing this without a sort of daughter board looks quite unfeasible with standard products you can find on the market for cheap. you will need some sort of customized display.