Memory regions of nRF52 linker script

[monpetit]

I'm faced with a curious problem.

The examples of nRF52 SDK 0.9.2 have linker sciprt like this:

/* Linker script to configure memory regions. */

SEARCH_DIR(.)
GROUP(-lgcc -lc -lnosys)

MEMORY
{
  FLASH (rx) : ORIGIN = 0x0, LENGTH = 0x80000
  RAM (rwx) :  ORIGIN = 0x20000000, LENGTH = 0x8000
}

INCLUDE "nrf5x_common.ld"

Or like this with SoftDevice:

/* Linker script to configure memory regions. */

SEARCH_DIR(.)
GROUP(-lgcc -lc -lnosys)

MEMORY
{
  FLASH (rx) : ORIGIN = 0x1f000, LENGTH = 0x61000
  RAM (rwx) :  ORIGIN = 0x20002800, LENGTH = 0x5800
}

INCLUDE "nrf5x_common.ld"

The RAM length of these linker scripts are all 0x8000, i.e. 32 KB. But nRF52832 has 64 KB RAM. Why they differ from the specification? Can I modify the length of them to 0x10000 (64 KB)?

[Håkon Alseth]

Hi,

If you have the "engineering B" of nRF52832 (the PCA10040 DK, and not the nRF52-PreviewKit PCA10036), then you can safely expand the RAM area to 64K.

The first engineering sample "A" had an issue where one 32K chunk was located at a different area: infocenter.nordicsemi.com/.../anomaly_832_34.html

It still has 64K of RAM, but it's not located at the address it was supposed to be. This has been fixed in Engineering B.

Cheers, Håkon

[monpetit]

I see. Thank you. =)