nRF5340 QSPI and external PSRAM

[valeriy_simakov]

Hello,

I want to increase my RAM storage by using PSRAM like a cache for data which I can't send via BLE right now (poor signal quality) and I will send them letter.
I should save about, 6400B in 100ms. Total amount of data, about 5MB, in the worst case scenario.

As I understand, nRF5340 doesn't support external RAM (need driver?), only external flash. 

My questions:
1. Is it possible to write a driver, or it's a hardware problem?
2. If (2) is a hardware problem, could you please recommend me another solution for external storage. 

[Turbo J]

Read the QSPI chapter in the PS, this peripherial is tailored around a specific set of NOR flash chips with hard coded commands. Not sure if it is possible to use a PSRAM chip here.

Your use case sounds like you could use regular SPI and just (Easy-)DMA the data in and out manually. A MicroSD card may be cheaper than a PSRAM chip in the MB range.

[valeriy_simakov]

Thanks for your reply!

[valeriy_simakov]

Hi,
The project has been suspended for a while and now we want to continue)
So, we want to use NOR flash, as external storage. 

Infineon-S25HS256T_S25HS512T_S25HS01GT_S25HL256T_S25HL512T_S25HL01GT_256_Mb_512_Mb_1_Gb_SEMPER_Flash_Quad_SPI_1_8_V_3-DataSheet-v69_00-EN.pdf

But as I understand from datasheet we nRF supports only hardcoded instruction set (table 119, NRF5340-QKAA-R7_Nordic_Semiconductor_ASA). 
Could you please verify the compatibility with flash above?

[Sigurd Hellesvik]

I can not download the datasheet somehow. Can you try to upload it again, maybe with a shorter PDF name?

[valeriy_simakov]

OK
Infineon-S25HS256T.pdf
Or by link:
www.infineon.com/.../Infineon-S25HS256T_S25HS512T_S25HS01GT_S25HL256T_S25HL512T_S25HL01GT_256_Mb_512_Mb_1_Gb_SEMPER_Flash_Quad_SPI_1_8_V_3-DataSheet-v69_00-EN.pdf