STM32F429VG support 24-bit LCD TFT?

Posted on October 18, 2014 at 13:51

I'm not sure what exactly you want to happen here, the parts share a common die, with reduced functionality bonded out as the pin count drops. The STM32 family, and frankly most similar devices, generally have more peripheral functions than can be escaped from the chip all at once.

As a designer it's incumbent on you to determine which device is going to provide the required pins and function you need to execute. For any STM32 design where you expect to use wide LCD interfaces and wide external memory devices you're going to have to start with 144 or 176 pin devices.

Posted on October 18, 2014 at 15:38

Clive1,

Thanks your help. Actually I want to us 100 pin 429 to design a small control system with 7'' TFT LCD, because only 429xxx devices have TFT LCD interface. I do not  use any external devices except LCD. So I think 100 pin 429 chip is enough for me.

Unfortunately, I can not find all 24 RGB pins in LQFP 100 pins layout, such as LCD_B1, LCD_R0 and R1.

But 429 datasheet says all 429 devices support TFT LCD RGB888. So why? I am eager to know 100 pins 429 can reach my purpose. 

Thanks again. 

Raymond

Posted on October 18, 2014 at 16:28

If the documentation indicates the pins you need aren't escaped there is nothing that can be done to resolved that. These are design decisions made by ST and committed in silicon.

Some of the choice made are poor, and one wonders why they were made, but for small and full featured designs they will point you to the BGA packages (PCB and manufacturing costs/complexity pushed to the user of the part).

I'll observe that the STM32F429I-DISCO is very limited because you can't get SDIO, DCMI or Ethernet out of the part cleanly.