How to use LTDC on ST32F767ZI to connect to LVDS interface on TFT-LCD display with touchscreen?

[Andrea Dall'Era]

Posted on July 13, 2018 at 19:48

I'm a beginner; i want to use STM32F767ZI board to connect it to an TFT-LCD 10,1' display with capacitive touchscreen like this

https://www.mouser.it/ProductDetail/Newhaven-Display/NHD-101-1024600AF-LSXV-CTP?qs=%2fha2pyFadugDeaZ93%252bxmjltF5XnL1tuKKeKhr6ozQlyjykXYzK%2fMy1hDi5YYw7DF

 .

First if is possible i want to know a link that explain to me the protocol that i need to be connected to an LVDS-display.

I read stm32 (not completly) doc en.STM32F7_Peripheral_LTDC.pdf and en.DM00287603.pdf(AN4861).

In this doc i find that LTDC give out data in parallel mode:

* if i want to connect to an LVDS dispaly i need a chip to translate the information?

#ltdc-to-lvds-display?

[T J]

Posted on July 16, 2018 at 00:59

wow that is so expensive...  and not Mipi, so I think you are barking up the wrong tree there...

check this brand:

https://www.buydisplay.com/default/tft-display/10-1-inch

 

LVDS is easy to use but be careful with track layout, its 6/8channels x 300MHz or there abouts...

do you need a super active display ?

you can go a little bit slow with this one :  Also not Mipi.

https://www.buydisplay.com/default/serial-spi-i2c-10-1-inch-tft-lcd-module-dislay-w-ra8876-optl-touch-panel

 

this is your selected display: how many LVDS channels ?  4+clock

now check the processor:

The DSI Host is a dedicated peripheral for interfacing with MIPI® DSI compliant displays.  <- your issue

? Maximum resolution of 800x480 pixels:

? Maximum resolution is limited by available DSI physical link bandwidth:

? Number of lanes: 2  (You need 5 channels for LVDS...)

? Maximum speed per lane: 500 Mbps1Gbps

[MSanc.14]

Hello, I want to use the same STM32 MCU to controll a TFT with LVDS interface, so I don't know how I should connect the TFT pins into the MCU.

There are a MCU that have a LVDS pins that connect directly with TFT or I need a Converter of LVDS to RGB connector to connect the TFT to RGB pins in order to use LTDC library?

I put here the datasheet of TFT: https://eu.mouser.com/datasheet/2/271/Microtips%20Technology-8-28-2017-MTD0801PZL%20spec1-1181493.pdf

[T J]

This is an LVDS display,you need a RA8877 chip, or something like it.

60MHz pixel clock will be ok.

[Microstar]

Use a RGB interface TFT or add a RGB to LVDS chip. EXP. TI DS90C385​

[MSanc.14]

I use a RGB to LVDS conversor, but i have an other question, I want to use the BSP library from STM32F429 discovery which have a tft. So the BSP use the code of the ili9341 (ili9341.h/ili9341.c) device, I know I should rewrite the part where are the specification of the tft default. But I don't know if I should rewrite the rest of the code (Level 1 command, etc). I don't know if this part of code it is used by BSP library or what is his funcion in the code.

[RRoon]

@MSanc.14​ @Andrea Dall'Era​ 

Did you ever get this RGB to LVDS circuit working ?

Can you share your findings ?

Regards, Richard.

[Andrea Dall'Era]

​at this time i stop to work on it, i have no idea when i restart