Problem reading-writing on HyperRAM connected to flexSPI interface on iMX8 processor

[priyank_bhatt]

Hello,

I am working on iMX8QXP based custom board with L5.4.24-2.1.0 and trying to interface an Octal RAM on its FlexSPI interface. The command set of the RAM I am using is similar to the Cypress S27KL/S27KS series HyperRAM and a PSRAM APS6408L-Ocx from apmemory. This has confused me whether I should use a spi-nor driver or hyperbus driver or make my own.

I have created a driver for Octal RAM "inspired" from spi-nor and fortunately, with few dummy cycles adjustment, I am able to read ID register and able to read-write to configuration register which are only 2 bytes long each.

My concern comes when I try to read-write data to/from memory. With dummy cycle adjustment I am able to read and write data to memory but I see many garbage bytes while reading.

I have learned that iMXRT1050 EVK has a hyperflash on board which is connected to the flexSPI interface. Also, I went through application note AN12239 How to enable HyperRAM with i.MX RT. I also went through the iMX RT SDK demo but it did not help to solve the issue I am facing.

Is there any document on how to communicate to hyperRAM using flexSPIwith iMX8 processors?

Has anyone else faced a similar problem?

Thank you

Priyank

[igorpadykov]

Hi priyank_bhatt

reason for read issues may be that for hyperRAM it is necessary to use specific for it

LUT table. Some details can be found in Figure 18-11. HyperBus device read transaction

i.MX 8DualXPlus/8QuadXPlus Applications Processor Reference Manual

Application note AN12239 also can be useful as it describes similar FlexSPI module.

Best regards
igor