The MDK installers add support for Nordic chips in Keil µVision 4 and IAR Embedded Workbench. It adds device header files, flash algorithms and system description files. If you use Keil µVison 5, you don't need to install these. When you open a project, you will be asked to install the required nRF_DeviceFamilyPack.
If you refer to the MDK installer packs in the SDK directory, you can see which MDK packs you have installed in "Programs and Features" in Windows Control Panel. If you refer to the Keil packs, you can see this in the Package Manager in Keil. If you want to see which files are added/edited by the MDK installer files you can run the installer from the commandline using the command: msiexec /i "MDK.msi" /L*V "example.log". This will create a detailed logfile describing every change that has been performed.
The system_nrf52.c file does not come with the SDK, but is installed as part of the MDK. For Keil µVision 5 the file can be found in [KEIL_INSTALL_DIR]\ARM\PACK\NordicSemiconductor\nRF_DeviceFamilyPack\[VERSION]\Device\Source
If you refer to the MDK installer packs in the SDK directory, you can see which MDK packs you have installed in "Programs and Features" in Windows Control Panel. If you refer to the Keil packs, you can see this in the Package Manager in Keil. If you want to see which files are added/edited by the MDK installer files you can run the installer from the commandline using the command: msiexec /i "MDK.msi" /L*V "example.log". This will create a detailed logfile describing every change that has been performed.
The system_nrf52.c file does not come with the SDK, but is installed as part of the MDK. For Keil µVision 5 the file can be found in [KEIL_INSTALL_DIR]\ARM\PACK\NordicSemiconductor\nRF_DeviceFamilyPack\[VERSION]\Device\Source
