
         Generating a new operating system on the SB180
         ----------------------------------------------

With all of the compile-time options available in ZCPR3, the user
may not be happy with the way his system was set-up by Micromint.
To modify any of these options, however, requires the user to change
one or more files, reassemble the modified portions, and regenerate
the operating system.  While not difficult, there are certain files
which must be present and steps must be done in a certain order.
The process of modification and regeneration will be described here.
Further details may be obtained from the book "ZCPR3: The Manual".

   1.  System regeneration is required only when modifications are made
       to the BIOS, or to ZCPR3.  Files such as FVC.Z80, or SYSRCP.Z80
       aren't integrated into the system, so may be changed independently.
       BIOS.Z80 needs the library files PORTS.LIB, Z3BASE.LIB, and
       SYSENV.LIB to be reassembled.  ZCPR3.Z80 needs Z3BASE.LIB and
       Z3HDR.LIB.  You should never have to make changes to the ZCPR3.Z80
       file directly since all the user selectable options are contained
       in the Z3HDR.LIB file.

   2.  Copy all the files you will need to a fresh disk.  This should
       include source files, associated library files, your text editor,
       and a copy of ZAS.

   3.  Make your changes to the source (or library) files.  Assemble
       them with ZAS to create .REL files (either BIOS.REL, ZCPR3.REL,
       or both).

   4.  Now it's time to generate a new system.  Rather than copy all the
       files you will need to a new disk one file at a time, it is easier
       to copy all of disk 4 (with FVC) and delete the files you don't
       need.  Make a copy of disk 4 and delete all the help files (use
       the command 'ERA *.HLP') to make some work space.  Copy your
       new .REL files to this disk, replacing any old files which may
       already be there.

   5.  You must also configure ZDM before it can be used in the
       generation process.  Run ZDM and tell it how wide your screen
       is as well as how many lines it has.  Be careful, it expects
       these values in hexadecimal.  A new file, called ZDI.COM, is
       then created and the program stops.  Rename this file to ZDM.COM
       so it can be used later. (Renaming the file will delete the old
       ZDM.COM file.  Since you still have your original disk to go back
       to, this is OK.)

   6.  Now you are ready to let the computer do its thing.  Simply
       type 'ZEX MKZSYS'.  This batch file links together a new system
       and creates the file MOVZSYS.COM.  Next, type 'MOVZSYS 56' to
       actually create the system image in a file called ZSYSTEM.MDL.
       To place the new system on the boot tracks of a disk, put a copy
       of SYSGEN.COM on this disk, type 'SYSGEN ZSYSTEM.MDL', and follow
       the instructions that appear on the screen.  Boot the new disk and
       you are running your new system. and f