SHELL <S16 Pathname>                                          Type: Internal

    Batch: Yes
 Keyboard: Yes
Wildcards: No

This command will execute a ProDOS 16 SYSTEM (S16) program while keeping
ECP-16 active and in memory.  If you just enter the name of an S16
program then ECP-16 normally shuts itself down and remains dormant.
With the SHELL command you can execute S16 programs from BAT files
provided that the S16 program doesn't close the BAT file being executed.