QSPI dual-flash memory mode with TouchGFX

[Soup]

I was wondering if it's possible to use dual-flash memory mode with TouchGFX, and if so is there any documentation available ?

[Andreas Bolsch]

What's the point here? QSPI single or dual flash mode just gives additional read-only memory mapped into address space of the CPU. Check the corresponding RM and firmware sources for e.g . STM32F769I-Disco, there you will see how to deal with memory mapped mode of QSPI flash.

Single vs. dual flash mode means only setting DFM bit in QUADSPI_CR register, incrementing FSIZE field in QUADSPI_DCR (and initialization of the additional GPIO pins in the very same way as those in single mode).

[Soup]

Hey, thanks for the reply.

I did set the DFM bit using the HAL libraries and also my total size (2 * 64Mb).

I assume i still need to change some DMA settings...

QSPIHandle.Init.FlashSize          = (26); // 128MB, FSIZE = 27-1
QSPIHandle.Init.DualFlash          = QSPI_DUALFLASH_ENABLE;

[Andreas Bolsch · Accepted solution]

In memory mapped mode you won't see any difference between single and dual flash mode (except for the memory size and faster transfer).

So no need to change anything else. Even if the flash needs some configuration during initialization in indirect read/write mode when both chips are of the same type: As all commands are send to both simultaneously, only the command parameters need to be "doubled". I. e. if you are going to read the status registers, the transfer length would be 0x1 (=two bytes) instead of 0x0 (one byte), and accordingly two bytes have to be read.

[Soup]

i've changed all my command parameters and also the transfer length according from what i've seen on the Disco example. I also checked my hardware configuration. Still not working as intended

[Soup]

I've finished this project today. The thing you need to remember is that the command parameters need to be doubled like Andreas said.

Look to the 69-Disco example and diff with a normal example so you can see the differences.