STM32F7 24-Bit TFT and SDRAM (No DQM lines)

dennis23 · ‎2015-12-13

Posted on December 13, 2015 at 21:16

Hi guys,

I am using the STM32F746ZGT6 with a 24Bit RGB-TFT and an external SDRAM memory.

In CubeMX I have seen, that I cant use the DQM lines together with the full 24-Bit wide bus for the TFT.

I want to use the SDRAM AS4C16M16SA. What disadvantage do I have if I do not connect the DQM lines? Or other question what is the best solution for using both parts together. It is okay not to use the whole memory, but I need a little bit external SDRAM memory.

Hope you can help me. Thanks!

-Dennis

#sdram #stm32f7 #dqm

dennis23 · ‎2015-12-17

Posted on December 17, 2015 at 15:41

Hi,

no idea anyone?

waclawek.jan · ‎2015-12-17

Posted on December 17, 2015 at 19:23

> What disadvantage do I have if I do not connect the DQM lines?

You won't be able to access the SDRAM bytewise, halfword-wise, nor at unaligned addresses.

What are the ramifications of these is up to you.

Why don't you simply try this on the DISCO board? Simply set the DQM pins to GPIO outputs and set them low.

JW