STM32F4 FSMC What is BusTurnAroundDuration and DataLatency

[Cobus Hoffmann]

Posted on February 21, 2017 at 08:40

I am trying to setup my stm32f4-discovery board to work with an ili9341 TFT LCD. I have finally figured out how to use the FSMC to do this in 8080 parallel interface (thanks to lots of help and coffee).

I am now facing the challenge of setting up the timing, but I am unsure what BusTurnAroundDuration and DataLatency refers to, in setting up the FSMC timing. 

Any help would be greatly appreciated.

Below is an image of the desired timing for the ILI9341.

I am using the following setup timing for my stm32f4

However I am aware that I can use Timing.CLKDivision = 16 to slow the HCLK for my FSMC timings.

#smt32f4-fsmc-tft #fsmc-timing #stm32f4-discovery #fsmc-sram

[Oliver Beirne]

Posted on February 21, 2017 at 12:55

Hi Cobus

I have moved your question to the

https://community.st.com/community/stm32-community/stm32-forum?sr=search&searchId=49afe7af-d0bf-47c8-aac4-8dab434939df&searchIndex=0

‌ where someone should be able to assist you.

Thanks

Oli

[Cobus Hoffmann]

Posted on February 21, 2017 at 13:35

Thank you very much. How do I access it now?

[waclawek.jan]

Posted on February 21, 2017 at 15:09

I don't use Cube nor other 'library', but these probably refer to DATLAT and BUSTURN fields in FSMC_BTRx (and FSMC_BWTR for BUSTURN, where appropriate).

DATLAT is relevant for synchronous access only, which is probably not your case. BUSTURN is relevant for back-to-back accesses, with is probably not your concern either.

The FSMC (and FMC) chapter of RM is not famous for being very descriptive but it's still the best place to start.

JW

[Oliver Beirne]

Posted on February 21, 2017 at 14:15

Either through the direct URL (which stays the same as before) and also via your inbox which will update whenever a reply is received to this thread. Hope this helps .

[waclawek.jan]

Posted on February 22, 2017 at 01:45

I meant FSMC chapter in

http://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf

, the STM32F4 Reference Manual.

JW

[Cobus Hoffmann]

Posted on February 22, 2017 at 01:14

I have gone through those datasheets and all they mention is the following