Mpi3508 GPIO HDMI screen

mpi3508 GPIO HDMI screen.
The question is:
If I use an All-in-one Zynthian board (with MCP23017), can I use a generic mpi3508 GPIO display via GPIO?
My full setup is:
pcm5102 audio DAC- this one uses pins:

SCK         > Not wired (Internally generated)
BCK         > PIN 12    (GPIO18)
DIN         > PIN 40    (GPIO21)
LRCK        > PIN 35    (GPIO19)
GND         > PIN 6     (GND) Ground
VIN         > PIN 2     (5V)

MCP23017 uses:
Pin 3     >  GPIO 8
Pin 5     >  GPIO 9
Pin 8.    >  GPIO 15
Pin 10.   > GPIO 16
Pin 36.   > GPIO 27
Pin 37.   > GPIO 25

The reason why I want to connect the screen with a use of GPIO instead of HDMI is that I HDMI option requires an HDMI cable that will not fit inside Zynthian case, and a usb touch screen cable, that will not fit inside the case either.
The case I’m using is a 3D printed version from zynthian-case/3DPrinted_Waveshare35 at master · zynthian/zynthian-case · GitHub

An MCP23017 All in one board I’m using is:

Previously I’ve used a diy plywood case that was quite larger and the 2 RPI4 hdmi sockets, RPI audio 3.5 socket were not exposed. So all the connections and wires were inside the case.

Hi @sinitsinmike, I guess there will be no GPIO conflicts as the display use HDMI for the video signal (other 3.5 inch displays usually use the SPI interface wich “consume” a couple of GPIOs).
But I’m not 100% sure about this as the documentation lacks informations about this.

Hello. I specifically need to use GPIO for video, not HDMI, becasue those cables are sticking out of the case. When using gpio there’ no cables sticking out outside the case.

This display use HDMI for vidéo signal.
Thé GPIO header is for touchscreen and power supplu feature

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I guess I’ll have to order a different one :slight_smile:

For what it’s worth: There are a lot of choices for HDMI, USB and Ethernet to use flat and-or slim cable:

or just google “flat hdmi cable”.

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Thank you!
I kind of set my mind on a specific case. Wanted nothing hanging outside that case. Perhaps this is not possible. Perhaps I have to look at other 3d printed cases.

May be I can get a display that connects with a flat ribbon cable from LCD to the special connector on PRI board.

About these HDMI connectors, they exists in 90° or -90° too wich consume less space but from my experience the little plastic lock is really fragile (I have broke a couple of them) and I finally found that solution not so convinient and a bit expensive.

because, for quiet the same price of a 3.5 inch 480x320 display you can get a 5 inch DSI 800x480 dsplay.
Only one flat cable is needed for power touch and video signal: