Nanopi M4 touchscreen?

[qtwitty]

I had already bought Nanopi M4 and need touchsreen wich will work with that board on Android. Maybe, someone know about compatibility of that touch with Nanopi M4. For example, i read abought official touch HD 702 https://www.friendlyarm.com/index.php?route=product/product&product_id=165, but on spec there isn't info about compatibility with Nanopi M4, but that Technology ''One - Wire'' confuse me.... Maybe, someone know about compatibility of that touch or maybe other touch, that will work with SBC on Android (or how to do that they will work). Thanks in advance for community reply.

[v8dave]

From what I can see, there is no actual LCD module available from FA that is plug in for the M4. The T4 has an eDP interface but the M4 is either HDMI or you could use the MIPI DSI interface with a custom interface to an eDP display. You would have to check the specification of the DSI LVDS lines to see if they match with the eDP inputs and signal mapping.

Either way, you will need to know how to modify the kernel and u-boot to support the LCD interface. I'll have a look through the Android kernel for the T4 (basically same as M4 as far as I can tell) and see what is hidden in there for display support.

I've just completed development of a custom LVDS interface for a 1024x600 IPS 7" LCD for the Nano PC T3 Plus so it is possible to do all of this if you have the knowledge of PCB design and kernel hacking.

1-wire is just a simple way for FA to control the LCD brightness and touch but that was mainly for the older resistive touch panels as capacitive uses the I2C bus so the 1-wire is mainly left to support the automatic detection of the LCD through an ID that each LCD transmits when requested to do so and takes care of the LCD brightness.

[qtwitty]

I am very apreciate for you reply. So small community and even smaller in regard of people who have a knowledge in all aspects including PCB design and Kernel hacking, and i am from that group (.
But i want to have a touchscreen so i have some questions:

1. you could use the MIPI DSI interface with a custom interface to an eDP display. You would have to check the specification of the DSI LVDS lines to see if they match with the eDP inputs and signal mapping.

2. Either way, you will need to know how to modify the kernel and u-boot to support the LCD interface. I'll have a look through the Android kernel for the T4 (basically same as M4 as far as I can tell) and see what is hidden in there for display support.

1. M4 have only MIPI DSI and HDMI like i know, and i know that T4 has touchscreen HD702e with eDP, so you mean MIPI DSI to eDP adapter, or even to LVDS, if regarding what connection has a touchscreen?
2. I must take T4 firmware and look in it for drivers to Touchscreen (for example HD702e with eDP), then to do own image of firmware with that drivers?

Thank you in advance