Right now I am facing with the next issue:
I am using FSMC to drive an SDRAM (IS66WV51216) and an LCD (ILI9481 display). As I use only the SDRAM without TFT, the write and read works fine, but as I connect the display the write/read operations have interesting issues.
As I write 1k data in to the SDRAM from 0-1023 and as I read back the numbers are strange (0 0 1 1 7 7 7 7 23 23 ...).
But as I use only the TFT with FSMC it also works fine.
I use the next settings:
- NE1, NE2 -> PULL UP
- DATA [0 - 16] -> PULL DOWN
- ADDRES[0 - 18] -> NO RESISTOR
- NWE -> PULL UP
- NOE -> PULL UP
- A25 -> this is connected to RS pin of TFT (data or command selector) NO RESISTOR
The data pins from 0-8 bits are common as the NWE and the NOE pins.
The data widths of the devices:
- TFT => 8 bits
- SDRAM => 16 bits
So separately both device work, but as I would like to use them in one SW it does not work.
I am using STM32F417ZET6 uC.
Have anybody any idea what should I set up to solve this problem?