System disk 30 has a real command interrupter and but only few commands But they are user friendly. (a little like command.com) System disk 50 has 20 or so commands and a few program files.  System disk 50 occupies about 4000k of disk space, but can live in less than 16k of memory space At this level most of the commands are a Dos like commands. “Dinkit system disks” here for a while, as the first set must be lock in place to give this section a stable foundation.