Double click the file in Solution Explorer to open it.
;startup address
* = $0801
;create BASIC startup (SYS line)
!basic
;increase border color
inc $d020
;return to BASIC
rts
Copy the code above and paste it into your file.
The pasted code should look like this
Click "Build" in the toolbar (or press the corresponding key combination, default F7) to assemble the file. If everything went right the file should compile successfully.
Click "Build and Run" in the toolbar (or press the corresponding key combination, default Ctrl-F5) to run the file. If any changes were made since last time the compile is performed before running.
The emulator should open, load and run your program, change the border color and return to the BASIC prompt.