It is the default engine for older versions of Keil µVision and is often required to maintain bit-per-bit consistency in long-term support (LTS) projects. How to Get the Verified Download
If it’s missing, you can download the specific "MDK-ARM" maintenance package from the Keil website, which includes verified toolchains. Technical Specifications July 2020 arm compiler 506 update 7 verified download
Go to -> Manage -> Project Items -> Folders/Extensions . Click the "..." button next to Use ARM Compiler . It is the default engine for older versions
Once you have downloaded the verified package, follow these steps to integrate it into your workflow: Standalone Installation various Linux distributions (Ubuntu
Windows 7, 8.1, and 10; various Linux distributions (Ubuntu, RedHat). Installation and Integration