nRF5340 QSPI communication with a non SPI Flash chip

[curiousme]

Hi Team,

I’m using the nRF5340 Development Kit, and in our project, we have a custom slave device that communicates over QSPI. We’d like to interface this custom device with the nRF5340's QSPI peripheral.

To do this, we’ve modified the board hardware by cutting solder bridges SB10 through SB15 and shorting SB20 through SB25 as mentioned in the user guide, as required to disconnect the onboard flash and reroute the QSPI lines.

I’m currently attempting to perform read/write operations with our custom device, but haven’t had any success so far. Could you please confirm whether the nRF5340 Dev Kit can be used to communicate with QSPI peripherals other than the onboard SPI flash? If so, could you point me to any relevant driver code or documentation that could help with this integration?

[curiousme]

Also I found that nRF7002 device which can be interfaced to nRF5340 through QSPI but it has almost same commands as that of On board NOR Flash Chip. Can you please clarify if we can communicate with any other peripheral which has different command set instead of what we have for NOR SPI Flash?

[Sigurd Hellesvik]

Hi,

Could you please confirm whether the nRF5340 Dev Kit can be used to communicate with QSPI peripherals other than the onboard SPI flash?

The nRF5340DK can use the QSPI to communicate with external QSPI devices. See Solder bridge configuration for how to disconnect the external flash.

If so, could you point me to any relevant driver code or documentation that could help with this integration?

 I think you should be able to use the Zephyr SPI drivers with the QSPI in genera, but if you want to use it for flash, that will be another driver.

curiousme said:

Also I found that nRF7002 device which can be interfaced to nRF5340 through QSPI but it has almost same commands as that of On board NOR Flash Chip. Can you please clarify if we can communicate with any other peripheral which has different command set instead of what we have for NOR SPI Flash?

See the nRF5340s QSPI instruction.

 Regards,
Sigurd Hellesvik

[curiousme]

What I understand is to use the existing SPI Driver itself to work like QSPI functionality by using CONFIG_SPI_EXTENDED_MODES with quad lines. If this is the case then what is the use of QSPI interface itself, why can't it be used directly by use of solder bridges as mentioned above instead of using the SPI? For SPI interface SPIM_SCK - P0.8, SPIM_MISO, P0.10, SPIM_MOSI P0. 9, and CS P0.7 pins are used. If we use the quad lines then P0.9 will act as IO0, P.10 will act as IO1 then which lines should be used for IO2, IO3 lines?

[Sigurd Hellesvik]

I dont think I understand your question completely, but:

The nRF5340 does not have a lot of restrictions on Pin Assignements. For QSPI, you are locked to some pins, but if you want to use normal SPI, you should be able to use other pins I think.