DEFT Shell

DEFT Shell is a menu driven program loader for use with the RS DOS and
machine language programs, such as the DEFT Pascal Workbench. It will
run on any Color Computer with at least 64K of memory and one disk
drive.

DEFT Shell consists of three programs, along with their data files. The
three programs are '*/BAS', 'Shell/BAS' and 'Shell/BIN'. The */BAS
program is a BASIC program that pokes in an ON ERROR GOTO routine and
sets up the memory as called for in the DEFT manual. It then runs the
program Shell/BAS. This program will load the Shell/BIN program and
execute it. It loads and EXEC's any programs selected by Shell/BIN, and
will restart Shell/BIN after each execution of a program. If the disk
containing Shell/BIN is not in drive zero on startup, it will ask for
the disk containing Shell to be inserted. Shell/BIN is a compiled Pascal
program, written using the DEFT AGS library. It allows selection of
programs from menus, along with the ability to KILL files and use
different fonts. It can be operated by the keyboard, joystick, X-Pad or
mouse.

Using Shell

When first started, the screen will clear to a checked pattern and the
preferences file 'Preferen/DAT' will be read. If this file cannot be
read, some assumptions will be made. The device will be assumed to be
the keyboard and the font will be DEFTAGS. If the preferences file could
not be found, a new one is created and a message is displayed to inform
the user. After reading the preferences, the font file will be read in
and the copyright notice will be displayed.

The directory will be read from drive zero and the menubar will placed
at the top of the screen. The following choices are available from the
menubar: TCE: This will display a menu of choices to find out
information about the Shell and the DEFT AGS system. File: This displays
a menu that allows reading a directory, killing a file, EXEC'ing a
binary file and finding out information on a file. Aids: This menu
allows sending a formfeed to the printer, displaying the text screen and
setting the printers baud rate. Preferences: This menu allows setting
the preferences for the system Exit: This will exit to the RS DOS 'OK'
prompt. To return to the Shell, type 'RUN' ߯The File Menu

This is where you do most of the interaction with files. The first
choice on the menu is 'Show Directory'. This allows you to select what
drive's directory is displayed on the screen. A menu of drives will
appear. Select the drive, and the directory will be read from it. If the
directory is unreadable, an error message will be displayed and the
directory from drive zero will be read. Next on the menu is 'Kill a
file'. This will ask you to select the file to be killed. THe menu will
clear and the cursor will move to the directory area. Place the cursor
on the file you want killed and press the button. If you select an empty
box from the menu, then nothing will be killed. The program will ask you
to confirm, giving you the chance to change your mind. If you confirm
the file will be killed from the disk. If the disk is write protected
the file will not be changed. After killing the file the directory will
be redisplayed and the command completed. The next entry allows EXEC'ing
a binary file from the disk. You will be asked which drive to EXEC the
file from. Select the disk that has the file you wish to EXEC. The
directory will be read and a list of binary files will be shown. Only
the first 14 binary files on a disk can be shown or selected. Select the
one you wish to EXEC, or select 'Cancel' to abort. If you do not abort,
a message asking you to wait will be displayed, and the file will then
loaded and executed. Show Info will allow you to find out more
information about a file. Select the file you want information on. A box
will appear on the screen, telling you the file name and extension, file
type and size in grans. Press the selection button when you have
finished with the information.

The Aids Menu

The Aids menu allows you to perform a few handy functions. The first is
'Page printer'. This will send a CHR$(12) (form feed) character to the
printer. This can be useful after printing a file with another program.
The next option is 'Show text screen'. This will display the normal text
screen. Press the selection button to return to the Shell. Why would you
want to display the text screen? It can be handy to see whatever was
printed by the last program you executed. For example, when using with
the DEFT Workbench, you can start the compiler, etc... and come back
when they are done. Viewing the text screen will allow you to find out
the number of errors produced. The last option is 'Set printer baud
rate'. This allows you to set the speed at which you talk to the
printer. This value can be stored in the preferences file, and it will
be set automatically at startup. The current baud rate is inticated by a
checkmark preceeding it. ߯The Preferences Menu

Preferences allows you to set the way that the the program interacts
with you. First on the list is 'Set printer baud rate'. This works the
same as this selection in the Aids menu. This value is read in from the
preferences file at startup. Next is the 'Input device'. This allows you
to select the keyboard, a HiRes input pack, a digitizer, or the left or
right joysticks. The current selection is inticated by a check mark. If
you accidentaly select a device that is not attached, such as a
digitizer, press the 'BREAK' key. This will return control to the
keyboard. Important note for CoCo 3 users: DO NOT SELECT the HiRes input
pack. It is addressed at the same memory location as the GIME chips
registers, resulting in unpredictable behaviour. Following that is the
'Screen mode' choice. This will allow you to use screen mode 0 or 1.
Mode 0 will use green and black colors, while mode 1 uses white and
black. The current mode is checkmarked. Next choice is 'Screen Font'.
This will ask for the drive to read the font from. Select the drive from
the menu. The directory will be read and a list of fonts will be shown.
Only the first 14 fonts on the disk can be used. Select the font to use,
or select cancel to abort. If a font is selected it will be read in from
the disk. That font will now be used for all displays. Finally, we have
the 'Save Preferences' selection. This will save all of your preferences
(Screen font, mode, input device and baud rate) into the file
'Preferen/DAT' on drive zero. This file is read at startup by the Shell,
allowing automatic setting of the input device and font to your choice.

Notes

Only the first 26 files in a directory are shown on the screen, and only
the first 14 binary files or font files can be selected by the EXEC and
Screen font commands. If for some strange reason you have a binary file
or font file named 'Cancel' you will not be able to select it. This is
because this name is used internally to the program for control. Any
binary files that are EXECuted should load in the memory between $1388
and $7FFF. Files that load below this range may not load properly, and
will definitly not return to the Shell when they complete.