Octal PSRAM on the SLN-SVUI-IOT board

[slawojka]

Hello,
I'm using the voice SLN-SVUI-IOT board.
community.nxp.com/t5/Mobile-Robotics-Knowledge-Base/SLN-SVUI-IOT-Turnkey-solution-introduction/ta-p/...
Due to limited on-chip RAM, I'm trying to launch an external Octal PSRAM memory on-board (APS6408L-OBM-BA), by default it's not enabled in the reference projects from github.com/NXP/mcu-svui

So far, based on the mimxrt685audevk_flexspi_psram_polling_transfer example, I've almost successfully enabled this memory, but with one issue:
Even address writes and reads work correctly (like int32), but not aligned (like int8) don't, data is corrupted.

Meantime, looking for a solution, I found NXP AN13028 Advanced HyperRAM/PSRAM Usage on i.MX RT doc www.nxp.com/docs/en/application-note/AN13028.pdf 
Within there is a summarization that some i.MX RTs won't work correctly with this memory, including RT1060:
"For QSPI PSRAM devices, all RT series can support
well, while for Octal SPI PSRAM, only RT1010/RT1170 and all RTyyy products can support well."

Does it mean that the RT106V on the SLN-SVUI-IOT board will not work with memory mounted on this board?
Or RT106V is not affected by the addressing issue and my problem is elsewhere?

[EdwinHz]

Hi @slawojka,

The RT106V should support the on-board APS6408L-OBM-BA. As you might have already noticed, the OPI-DDR PSRAM is connected on FlexSPI2, while the QSPI NOR Flash is connected on FlexSPI1. The issue might lie on an improper initialization and usage of the FlexSPI2 module.

Although the RT600 can be a good reference because it has the same on-board APS6408L-OBM-BA, it only has one FlexSPI module. Perhaps looking into the "evkmimxrt1064_flexspi_nor_internal_polling_transfer" example code from the RT1064 SDK might help to ensure that the FlexSPI2 module is set up properly. That said, this example sets up the FlexSPI2 module for the RT1064's internal Flash, not RAM.

Also, take a look into this document, which describes in more depth the FlexSPI differences and handlings between the RT1060 (which includes the RT106V) and the RT1064: Migration Guide from i.MX RT1060 to i.MX RT1064 (nxp.com)

BR,
Edwin.

[slawojka]

Thanks for the answer, it's great to read that RT106V should handle this memory.