Name: Capture 83
Author: Ian Graf (ian_graf@geocities.com)
Version: 1.2
Platform: TI-OS
Language: TI-83 Assembly
Memory: 393 bytes (not counting ZASMLOAD)
Release Date: 9/21/98


I. DESCRIPTION:

     Capture 83 is used to "capture" the contents of you calculator's
screen by communicating directly with the LCD, and storing the data to
Pic1.
     Capture is what is referred to as a "program size interrupt." This
means that when you run Capture your calculator goes into interrupt
mode two, and code is run every 200th of a second.


II. INCLUDED FILES:

     capture.83g
       - CAPTURE   Program (Run This)
       - ZCAPTURE  Object code
       - ZASMLOAD  Runs squished program

     capture.txt   This file

     zcapture.z80  The source

     capture.inc   Custom include file


III. INSTALLATION:

     1) Send capture.83g to your calculator
     2) Run prgmCAPTURE


IV. USAGE:

     To capture your screen you must first run prgmCAPTURE. You will
see the message "Capture 83 by Ian Graf Enabled." Now whenever you
press [LN], the contents of the screen will be saved to Pic1. To
disable Capture simply run prgmCAPTURE again. After you have captured
the screen you can view the contents of Pic1 by running prgmDISPLAY.
     You can capture the screen from anywhere in the calculator. But
for any reason the calculator could lock up if you capture the screen
while an assembly program is running. The most common reason for this
is that the interrupt vector and routine are copied to the APD buffer.
Many programs use the APD buffer as temporary storage. If they
overwrite the interrupt vector or routine, it will lock up the
calculator. In order to find out what programs are compatible with
Capture you will have to experiment and be prepared to take out your
batteries.
     Capture stores the screen to the first pic it finds in the VAT. To
keep it from storing to any pic other than Pic1, delete all the pics on
your calculator before you run Capture. Pic1 will then automatically be
created by Capture. If you delete all the pics on your calculator when
Capture is running and you try to capture the screen, your calculator
will lock up.
     It is perfectly fine to turn off your calculator or have it APD
while Capture is enabled. DO NOT reset your memory while Capture is
enabled. Doing so will lock up your calculator.


V. BUGS:

     As far as I know there are no bugs! If you experience a problem it
is most likely from another program writing to the APD buffer.


VI. CHANGES:

v1.2

     In this update a small problem with direct input was fixed. I
myself never experienced this problem, but it should be fixed.

v1.1

     In this update many optimizations have been made to the screen
grabbing routine. The screen is now captured so fast you should not
experience a delay of any kind. For the same reason you can now capture
the screen while in Ashell or mid grapher execution without any
problems.
     It is now near impossible to lock up your calculator from repeated
pressing of [LN]. Because the screen capture is so fast you can
repeatedly press [LN] or any other keys without any adverse effects.
There is also a key repeat guard so the screen will only be captured
once when you press [LN]. Without the guard, the screen could be
captured anywhere from five to ten times before you let go of the key.
     This version also comes with a small basic program that turns off
the axes, clears the screen, and displays Pic1. With this and the
improved performance, Capture takes up 36 more bytes than the older
version.


VII. CONTACT:

     If you have any questions, comments, or bug reports please feel
free to e-mail me.

     E-Mail: ian_graf@geocities.com
     Site: http://www.geocities.com/SiliconValley/Bay/7196/


Do not separate this document or any included files from Capture!
Capture 83 Copyright (C) 1998 Ian Graf
