Compiling software for both NRF52832 and NRF52840

[smackenzie]

I am currently developing firmware that needs to run on both 32 and 40 chips.

The basics of the situation is the firmware contains 3 'applications'. A flag in the UICR region determines what app should be loaded. One of these applications will be running on a 32 chip, the other 2 will be running on 40s. The main feature needed from the 40 is QSPI support, it uses the NRF_FICR->INFO.PART to make sure that the 40-specific features are not used on the 32.

The optimal outcome of this would be running the same softdevice and firmware on both chips. 

Would there be any issues running the 40 soft device on the 32 chips, assuming that no 40-specific features where used on the 32? (or vice versa)

My current thinking is to use the s40 and using a linker script similar to the 32 to make the compiler happy with the memory and flash regions when programming, and so the 40 features are enabled at compile time, tne verify the chip type at runtime.

[Keith Brafford]

For this to work, you are going to have to handle the different errata that get applied before main() is run also.  See arm_startup_nrf52840.s & system_nrf52840.c and arm_startup_nrf52832.s & system_nrf52832.c, respectively.

[AndreasF]

Hi.

It is not possible to run S140 on nRF52832, and there is mainly two reasons for this:

1. The radio in nRF52832 is simpler and does not have support for the features of S140.

2. nRF52832 is not certified to run S140.

So you have to run S132 on nRF52832 and S140 on nRF52840.

Best regards,

Andreas