Flash Spinor Non Volatile register

jonh1092 · ‎08-29-2023

Hi Community, I'm working with an I.MX 8DualXLite and I have tried to configure the Non-Volatile Register from MX25UW6445G which is a 64Mb bits interface Serial NOR flash memory, The register address according to the manual information is 0x40000000, and the factory default bits are set as 0xFF, I'm trying to read in this address but I'm getting a "0" as value but It should be a 0xFF, also the manual information indicates that only is possible to read in "normal read mode" where the device comes from Hardware Reset, Power on, command reset and exit from Program Erase or Write register mode, I'm trying to read from Power On and also by Hardware reset besides to make a validation of the status of a negative write register, It should be mentioned that I am able to read and write to the volatile register, maybe I'm ignoring something in the NV configuration.

JorgeCas · ‎08-30-2023

Hello, I hope you are doing well.

Could you please share me the steps you are following to read the register?

Best regards.

jonh1092 · ‎08-30-2023

Hi @JorgeCas ,

I'm following the next steps:

1.-Validate a negative write-in progress.

2.-Validate a negative Write Enable Latch.

3.-Setting SPI configuration and the register 2 address of the NV (0x40000000)

4.-Sending the configuration sequence to read with the corresponding OPI command set.

5.-Performing an API to read the SPI buffer externally.

6.- Printing the reading of the register.

With this same configuration for volatile register I'm able to read the value, actually I'm able to write in the register address and read what I'm writing but none NV.

JorgeCas · ‎08-31-2023

Got it, thank you for the clarification.

So, you are able to read/write on other memory address but not on NV registers, right?

Even when you read a "0" value, do you have the expected behavior when you write on that NV register?

Is there the possibility of "always return a zero value" behavior for that specific register? I do not have access for the reference manual of that specific part number.

Best regards.