spi_nor: Device id 00 ef aa does not match config ef aa 22

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Håkon Alseth — Tue, 12 Aug 2025 07:16:55 GMT

Hi,

I am glad to hear that you found a solution, and things are running as they should now!

Kind regards,

Håkon

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Mike Zhao — Mon, 11 Aug 2025 17:01:58 GMT

The firmware is now functioning correctly after implementing a workaround for an incompatibility between the nRF Connect SDK and the Winbond W25N02KV SPI NAND flash chip. Hardware diagnostics confirmed all pins are working properly.

Root Cause: The issue stems from a protocol mismatch in the SPI communication. The nRF Connect SDK's standard spi_nor driver is not directly compatible with the W25N02KV chip's response behavior.

The driver's spi_nor_read_jedec_id function sends a command and expects an immediate 3-byte device ID in reply.
However, the W25N02KV chip responds with a single dummy byte before transmitting the 3-byte ID.

This behavior is consistent across all read operations, causing data misalignment.

Resolution: A successful workaround was implemented with the following code modifications:

The spi_nor_read_jedec_id function was modified to read and discard the initial dummy byte before processing the device ID.
The application-level flash_read functions were also updated to discard this leading dummy byte from the incoming data stream.

These changes have resolved the issue and restored full functionality.

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Håkon Alseth — Mon, 11 Aug 2025 14:21:32 GMT

Hi,

Have you scoped the SPI pins to see if they behave as expected, ie. correspond with the log output?

Can you please share what changes you've done to the board files?

Kind regards,

Håkon

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Mike Zhao — Fri, 08 Aug 2025 16:47:56 GMT

Hi Hakon,

Thanks for your quick response.

As what you mentioned above, I also tried to add the following 2 lines to my prj.conf file, but the testing result is same. The firmware is still not able to read the manufacturer ID properly.

CONFIG_TFM_SECURE_UART=n
CONFIG_TFM_LOG_LEVEL_SILENCE=y

I config my board based on nRF9161DK_nRF9161_ns. For the detail, you can check test_spi_flash.zip which I uploaded early.

In my overlay file, I disabled the following devices,

******

&spi3 {

status = "disabled";

};

&uart0 {

status = "disabled";

};

&uart1 {

status = "disabled";

};

&uart2 {

status = "disabled";

};

&i2c2 {

status = "disabled";

};

******

I also redefined uart3 as following,

uart3_default: uart3_default {

group1 {

psels = <NRF_PSEL(UART_TX, 0, 4)>, <NRF_PSEL(UART_RX, 0, 5)>;

};

So, it should not have conflict configuration to P0.26 to CS#, P0.27 to CLK, P0.28 to MOSI, P0.29 to MOSO, P0.30 to WP# and P0.31 to HOLD#.

Do you have any advice?

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Håkon Alseth — Fri, 08 Aug 2025 13:12:32 GMT

Hi,

How do you build your board? Is it based on "nrf9161dk/nrf9161" board? If so, the UARTs are used for your pins:

[quote user=""]P0.26 to CS#, P0.27 to CLK, P0.28 to MOSI, P0.29 to MOSO, P0.30 to WP# and P0.31 to HOLD#.[/quote]

This means that any multi-image build must also have these uart's either redefined or disabled.

Did you try this?

[quote user="hkn"]If you use the board nrf9161dk/nrf9161, ie. the secure image of the board, does it work as expected then?[/quote]

Kind regards,

Håkon

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Mike Zhao — Thu, 07 Aug 2025 17:47:29 GMT

I run the spi flash sample firmware on nRF9161DK board without problem. I am able to read, write and erase the gd25wb256 NOR flash chip.

Follow your suggestion, I added the following 3 lines to my app.overlay file and did pristine build to the sample project. Flash the firmware to my customize board. The problem is same.

has-dpd;
t-enter-dpd = <3000>;
t-exit-dpd = <40000>;

*** <err> spi_nor: Device id 00 ef aa does not match config ef aa 22

From this error message, it seems that the code is able to read 3 bytes data from flash chip(W25N02KV), just the first byte is incorrect.

Do you have any other advice?

RE: spi_nor: Device id 00 ef aa does not match config ef aa 22

Håkon Alseth — Thu, 07 Aug 2025 08:46:34 GMT

Hi,

[quote user=""]nRF9161DK_nRD9161_ns[/quote]

If you use the board nrf9161dk/nrf9161, ie. the secure image of the board, does it work as expected then?

If yes, then I suspect there's a pinconflict between tfm and the non-secure app, which is usually the uart:

CONFIG_TFM_SECURE_UART=n
CONFIG_TFM_LOG_LEVEL_SILENCE=y

[quote user=""]The error is "spi_nor: Device id 00 ef aa does not match config ef aa 22". Somehow, the manufacturer ID is wrong. [/quote]

I do not know how this exact flash behaves, as I do not have it, but it might be that it boots up in a standby or sleep state?

Try adding DPD parameters, like done here:

https://github.com/zephyrproject-rtos/zephyr//blob/main/boards/nordic/nrf9151dk/nrf9151dk_nrf9151_common.dtsi#L211-L213

Kind regards,

Håkon