
The GRAPH system is designed to 
interface directly with CAD Version 2.2D
and later. You will notice many 
similarities between the two and, in 
fact, GRAPH does a lot of preparation 
that is not necessary for GRAPH but is 
necessary for moving from GRAPH to CAD.

To use the package LOAD and RUN "boot" 
from the GRAPH disk. The system will 
prompt you for the file disk drive. If 
you are using a two drive system the 
package will assume the file disk is the
drive that boot was NOT loaded from. If 
you are using a single drive system 
answer this prompt with the drive number
(normally 8). If you wish, you may 
change the default to a single drive 
configuration by listing boot and 
changing the definition of 'd1' in the 
second line of the program. This line is
REMed to show you what to change. The 
system will then load three support 
packages and prompt if you wish the 
present screen erased. The default will 
NOT erase the screen. You are then taken
to the main menu.

Bar graphs -> These routines will draw a
set of bar graphs either horizontally or
vertically. You can overlay as many as 
three sets of bars on the same graph. 
The system will prompt for the maximum 
value for the graph. This value must be 
at least as large as the largest value 
for the bars. If you wish, it may be 
larger...but if any of the bar values 
exceeds this value the system will 
return to this prompt and you will have 
to re-enter all data from this point on.
So make sure this is the largest value 
you enter. The system will then prompt 
for how many bars. Simply enter the 
number of bars you intend the graph to 
have. The system will next prompt for 
the layer. This feature allows you to 
draw bars on top of each other. Each 
layer is offset by a small amount from 
the previous layer. You should first 
draw layer #1, then #2, then #3. It is 
not necessary to use all three layers, 
and note that for each layer you must 
enter all the previous data again. After
you have entered the above information 
the system will go to the hires screen 
and draw the graph. When done...the 
system will remain in the hires screen 
until you press a key. To enter another 
set of bars press the same key you used 
to enter the routine initially ('b' or 
'B'). Note that you may switch hires 
screens with '!' and draw on the other 
hires screen. The graph drawn on the 
first hires screen is stored safely 
away, and can be recalled by pressing 
'!' again.

Pie charts -> This routine will draw a 
pie chart from the information you 
supply. You will be asked for the number
of segments and the percent for each 
segment. Note that the segment 
percentages must add up to 100%. The 
system will not ask for the last segment
percent, it will assume that whatever is
left of the circle is the last segment.

Functions -> The function routines will 
allow you to plot a function you enter. 
This function must be entered as a valid
BASIC equation. The routine re-programs 
itself to include this formula in the 
program. If the formula is not a valid 
BASIC equation the routine WILL crash in
the hires mode, and you will have to 
restart the program. The following are 
examples of valid equations to enter at 
the prompt:

3*x^2   try an x limit of 10 and a y 
limit of 300
sin(x)  try x limit of 6 and y limit of 
2
log(x)  try x limit of 3 and y limit of 
2

Any equation that can be entered in a 
BASIC program will work.
The only variable allowed in the 
equation is 'x'.

All BASIC functions should be 
permissible.
This routine can cause major headaches 
and if you are not familiar with 
programming in BASIC perhaps these 
routines are better left alone.

The print, load, and save routines are 
exactly the same as the commands for 
CAD. The routines for the Gemini printer
should support most Epson clones.

The major attraction of the GRAPH 
package is that it supports a direct 
interface with CAD. To use this 
interface choose 'C' from the menu. This
routine will set up some important 
pointers and variables for CAD and then 
prompt you to place the CAD disk in the 
drive and press a key. You can also go 
directly from CAD to GRAPH simply by 
putting the GRAPH disk in the drive and 
pressing a key. Make sure the CAD system
is not preparing to access the drive 
before you remove the CAD disk. You can 
safely exchange the disks when viewing 
any menu in the CAD system. If you go 
from CAD to the GRAPH system and draw a 
graph it is necessary to use 'C' to 
return to CAD as the variables and 
pointers mentioned before are destroyed 
by GRAPH.

In the event of a system crash press run
/stop-restore. The screen should blank. 
You will not be able to see the cursor 
or what you type so CAREFULLY enter the 
following:

sys64738

and press return. The computer should 
reset to a power-on condition. If you do
this without turning off the computer 
your hires screen should be intact. Just
load and run the boot program and pick 
up where you left off.

If you encounter any problems with the 
package or have any suggestions 
concerning improvements please pass them
along.

Any typographical errors in this 
document are the fault of my new Tandy 
102, not my battle-scarred veteran 
Commodore.

Steve Nye
70366,1316


