CMSIS-DAP is the official open-source ARM debugging emulator, supports almost all Cortex-M microcontroller core, do not pick manufacturers.
1. DAP emulator connected to a PC
2. Open the "Options for Target 'Target 1'" => "Debug", select "CMSIS-DAP Debugger"
3. Click the "Settings" button to open the "Cortex-M Target Driver Setup" dialog - select for simulation, click OK "CMSIS-DAP JTAG / SW Adapter" in
4. Click 
the compiled program downloaded to the development board package, click 
Start Debugging
