Code works on nrf51882 (16kb and 128kb) with RAM and ROM address of nrf51442 (32kb and 256kb)?

[soumil]

Hi,

I am burning the same code on two sets of chips nrf51882 and nrf51442. The nrf51882 chip is with 16kb RAM and 128kb of flash memory while the nrf51442 chip is with 32kb RAM and 256Kb of flash memory. I am using S110. The RAM and ROM settings in Keil are set to the following

ROM Size- 0x28000 ROM Start- 0x18000

RAM Size- 0x6000 RAM Start- 0x20002000

With these RAM and ROM settings, the code runs on the nrf51882 chip but the settings should be the following

ROM Size- 0x8000 ROM Start- 0x18000

RAM Size- 0x2000 RAM Start- 0x20002000

I am confused on how the code runs on the nrf51882 chip with the RAM and ROM settings not meant for it?

[Alex]

It means that your code doesn't hit neither RAM nor ROM limits of 16kb RAM and 128kb ROM. Once your code start using addresses over the limit you will have failure. With ROM you won't be able to load code, with RAM it won't run.