Use assemble.bat file to compile.  Ensure it
points to compiler.  Or, you can use the following
commands:

2500ad\bin\x64180 <filename without suffix>
2500ad\bin\link4 <filename without suffix>

Compile RTOS FIRST if changes made!!

At the prompt use 'D' to save listing to disk.
Enter 'Y' to generate a cross reference
Use 'HCS' as the input assembly file.
Use 'HCS as the output file.

When assembled...

Use 'HCS' as the input link file.
Enter CODE offset as '0'
Enter DATA offset as '8000'

Use 'RTOS' as the second input link file.
Enter CODE offset as <CR>
Enter DATA offset as <CR>

Enter <CR> as the third input link file.

Use 'HCSROM' as the output file.
Enter <CR> as the library file.

At the prompt enter <CR> for default format.

You should now have a HCSROM.HEX file