Persistent across power cycles variable storage with LPC54018 single SPI Flash

mitchkapa · ‎02-08-2023

Hi,

I'm using an LPC54S018 microcontroller with a 16 MB SPIFI flash. The application code is too large to fit into RAM and so I am using the XIP_IMAGE flag during compile. I need to store variables in the flash for access across power cycles. I have been following the steps listed in this forum post:

https://community.nxp.com/t5/Kinetis-Microcontrollers/STORING-VARIABLES-IN-FLASH/m-p/650092

but I can't modify the "test" variable once the code is running, because it is read-only. Is there a way to make the test variable read/write, and able to be saved across power cycles?

Thanks for your help,

Mitch

ZhangJennie · ‎03-07-2023

HI mitchkapa

If you want variable read/write, we must store it in RAM.

If you store it in SPIFI Flash, please refer spifi_dma_transfer or spifi_polling_transfer demo code in SDK folder to program the related address.

Thanks,

Jun Zhang