52840 external flash size

[WrightLin]

Hi Sirs:

I've searched 52840 specifications and devzone, but there is no related information about the maximum external flash size could be adopted on 52840.

Would you please give me a hint about where can I find the info? Thanks a lot!!

[Simon]

If you want to use XIP (Execute in place), which allows the CPU to execute program code directly from the external flash, the maximum external flash which can be utilized is 128 megabytes. This is documented in the infocenter, where the memory between address 0x12000000 and 0x19FFFFFF is dedicated for XIP.
However, I am not sure if there are any memory size limits beyond this. The QSPI module on the nRF5280 uses 32 bits registers for specifying respectively destination address and transfer length, which makes it possible to access a 4GB address space. I have not looked into how to access larger memory than that, but I am sure there exists methods.

Best regards, Simon