Can I connect off-the-shelf DSI display to an STM32 eval board?

[jhnlmn]

I need to connect a 5 inch 480x800 display to a STM32 eval board.
There are many 480x800 DSI display on the market, but all of them are designed for PI
and have standard PI 15 pin or 22 pin connector, which has 1 clock, 2 or 4 data pairs and SCL/SDA and +3.3V.

But STM32 eval boards like
https://www.st.com/resource/en/data_brief/stm32u5a9j-dk.pdf
or
https://www.st.com/en/evaluation-tools/stm32h747i-disco.html
use some unique DSI connectors and there are no displays for them.

Question is whether it is possible to connect to STM32 a display designed for PI.

The first part of this question is whether DSI clock and data pairs are compatible.
Second is what to do with other lines on STM32 DSI connector, like:
SCLK/MCLK, LRCLK, I2S, CEC_CLK, CEC, DSI_TE, LCD_BL_CTRL, DSI_RESET, TOUCH_INT, I2C4_SDA, I2C4_SCL.
I guess I2C should be compatible, but what to do with others?
Is it possible to make some simple adapter?

Thank you

[RhSilicon]

PI: Raspberry Pi

[KDJEM.1]

Hello @jhnlmn ,

You can connect the Raspberry PI displays through B-LCDAD-RPI1 adapter.

This B-LCDAD-RPI1 adapter board features up to two lanes of MIPI/DSI data and I2C interface support, and enables the use of extended displays with standard DSI interface on STM32 EVAL/DK board family.

For more information about the connection pins I recommend you to look to DSI to LCD adapter board (st.com).

Thank you.

Kaouthar

[RhSilicon]

> To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

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[KDJEM.1]

Hello @RhSilicon ,

Yes, the question is open and this text is displayed to push the community member to click on Accept as Solution on the post, which solved the issue or answered the question (once the question has been fully answered).

Thank you.

Kaouthar

[MM..1]

Try go back to start. You ask connect other pinout DSI to EVAL. Primary dont do it. DSI is suer high speed bus and require very perfect signal ways = every reduction ang long way is source for trouble.

For custom DSI create own custom board with STM and right connector.

Here one example 1280x480 

[RhSilicon]

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@MM..1 wrote:

Try go back to start. You ask connect other pinout DSI to EVAL. Primary dont do it. DSI is suer high speed bus and require very perfect signal ways = every reduction ang long way is source for trouble.

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I partially agree, see this:

In theory, the CSI/DSI interface isn't meant for super long cables, and you're not supposed to extend them. But we laugh in the face of theory. We connected two 1 meter long extension cables using this Thingy and our Display and Camera worked! But, just so you know, it's really not guaranteed: CSI/DSI are meant for maybe 25cm max length.

https://thepihut.com/products/adafruit-csi-or-dsi-cable-extender-thingy-for-raspberry-pi-ada3671

[MM..1]

I write source for trouble not impossible and maybe good is say DSI have low and high speed mode and command mode displays can only use low that dont have troubles with ...
And problem isnt lenght, but difference between lenght data and clock lanes plus changes in diferential line impedance...

[MIhde]

Here is an example that (at least for me) works with the official Raspberry Pi 7" display and the WaveShare 2.8" display.  The most important thing is you need to use an STM chip that can support 1Gpbs DSI lanes (i.e. STM32H747).