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                             Apoo Workbench
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The Apoo Workbench is an environment to monitoring the execution of a
Virtual Processor Unit.  During the execution of a program, it shows
the contents of the program counter, registers and memory data. The
program in memory is displayed in an Assembly language (not in a
machine language). As is usual with processor units emulators, Apoo
has two memory segments: the program-segment and the data-segment. In
this way, both addresses for program instructions and data will begin
in 0.

The Apoo Workbench allows also the editing/saving of the text program,
providing an easy way to write/edit/debug/execute Apoo assembly programs.


Execution
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To execute a program in the Apoo Virtual Processor Unit you must first or:

   - enter in Edit Mode and write its instructions
   - open a text file with its code

After that, you can Load it; if a "parsing error" occurs, enter edit mode
and correct it; the interface will show the text line in which the error
occurred.

When the program is loaded (in memory) you can execute it in three ways:

     - Run: will execute all the instructions 

     - Step: will execute the next instruction and the values of the
       program counter, registers and memory data will be updated; the
       next instruction line, if exists, will have the background
       white

     - Continue: will execute instructions until the next breakpoint

You may set or clear a breakpoint in an instruction by double-clicking
(with the mouse) on its line address number.

The button labeled Clear can be used to clear all breakpoints 

Edit Mode
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In edit mode you can change the text code of a program or create a new
one. To enter Edit Mode press the Edit button or New button.
After editing you can Save or SaveAs the current edited text.
You leave Edit Mode by loading the program (Load button) or opening a
new file.

Emacs key shortcuts are provided. They can be enabled on the Preferences
dialog and they get listed on the Edit menu.

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(C) 1998 Rogerio Reis, Nelma Moreira {rvr,nam}@ncc.up.pt