Cream of the Crop 1/Cream of the Crop 1.iso/CAD/PADSLOG.ARJ/LOGIC.EXE/MANUAL.LOG

Text File | 1992-01-16 | 62KB | 1,916 lines

INTRODUCING PADS-LOGIC


PADS Software, Inc. welcomes you to try our
PADS-Logic Evaluation Package. The
Evaluation Package is unique, because it is
the first schematic program to be provided
as Shareware. This means that the  Evaluation
Package is not simply a demo disk, but a
complete, working copy of PADS-Logic. It contains all
of the capabilities  of the commercial
program, and can produce a complete set of
netlists and drawings. It is only limited
in the size of the circuit you can create.

If you are like most engineers, you don't
have time to play with demo software, but
want to get your hands on the real thing.
With this package, you can create
schematics, make plots, produce net lists,
define library parts... all of the
functions of PADS-Logic.  Also, all
drawings, library parts, and layouts you
create can be read directly by the
commercial packages, so every minute spent
with this shareware is real work!

You may use this evaluation alone, or in
conjunction with the PADS-PCB Evaluation
Package.  Together, PADS-PCB and PADS-Logic
offer an excellent integrated engineering
tool.

The importance of a Multi-Sheet Database

PADS-Logic represents a new concept  in
low-cost schematic capture software.  Its
intelligent, multi-sheet database
introduces a new level of functionality  in
PC-based schematic packages.

 Other schematic packages will let you work
with only a single drawing at a time. PADS-
Logic lets you work with the entire circuit
at the same time: we call this our Multi-
Sheet Database. The advantages of a Multi-
Sheet Database include the following:
o       The entire circuit is in a single
file, so no matter how many pages are in
your schematic, you need to keep track
of only a single data file.
o      Because the entire circuit is in
memory, the software is able to keep
track of all gate and reference name
assignments automatically.  This gives
you two advantages: PADS-Logic
automatically assigns names and gates,
saving you a lot of typing; and if you
decide to assign the gates yourself,
PADS-Logic insures you cannot make a
mistake, like assigning a duplicate part
name or unmatched gates to the same
part.
o       Search and query functions are
possible across the entire circuit. You
can instantly access any part, sheet
tag, signal name, by simply typing its
name, and PADS-Logic will find the item
and display it for you.
o       Since your entire design is in memory,
you can quickly switch between sheets in
your design.
o       You don't need to do a cumbersome
batching of individual sheet files at
the completion of the design to generate
a net list .
o       Automatic on-line design checking is
inherent across all sheets of a circuit.

This manual has been written as a general
introduction to PADS-Logic, so most of the
key commands are described. We encourage
you to explore all of the capabilities of
PADS-Logic, so please try the commands not
described as well. Turn the page to start
investigating how the power of PADS-Logic's
intelligent, multi-sheet database can
reduce the design cycle on your next
project!

If you have printed this manual from the
ASCII file provided on the disk, and would
like a copy of the printed manual, you can
order  it from your local authorized PADS
Dealer or contact PADS Software, Inc.
(phone:[phone], fax:[phone]).



RUNNING PADS-LOGIC



The instructions for installing the PADS-
Logic evaluation software are found in the
separate Evaluation Installation Guide (or
in the text file INSTALL.DOC). After the
evaluation software is installed, it can be
run as either an automatic self-running
demonstration, or as an interactive design
tool.

Starting the Self-Running Demonstration

To start the automatic self-running
demonstration:
1)    Make \PADSDEMO your current directory by
typing:
CD \PADSDEMO<CR>
2)     Then type:
LOGDEMO<CR>
    The PADS-Logic self-running
demonstration will  start. This is an
automatic program that tells you about
PADS-Logic while running the actual
software. The self-running demonstration
shows the primary features of PADS-Logic
through a series of pop-up windows and
examples.  It is designed to give you a
quick overview of the PADS-Logic
features.  Several comments:
o      To pause the demonstration, press the
space bar.
o      When you are ready to continue again,
press the space bar again.
o      Messages will be displayed for a fixed
amount of time and are then removed to
continue the demonstration. If you wish
to proceed faster, select any key other
than the space bar.
o     To exit from the self-running
demonstration to the interactive
software, press Ctrl-X.  (While
depressing the CTRL key, select X).
o     To exit from PADS-Logic to the DOS
prompt, press Alt-X.  (While depressing
the ALT key, select X.)

Note: you may need to press Ctrl-X or Alt-X
several times to make them work.

Starting the Interactive PADS-Logic Program

Most users will want to use the software in
the design of real schematics to evaluate
the features of PADS-Logic. There are two
ways to start the  real working version of
PADS-Logic.
1)     First make the \PADSDEMO directory your
current directory by typing:
CD \PADSDEMO<CR>
2)     Then you type:
LOGICS<CR>
    to enter the program directly, or you
can type:
PADSGO<CR>
    to enter the PADS Command Shell, used to
select one of several PADS design
programs. To enter the PADS-Logic
program from the PADS Shell, place the
mouse cursor over the box labeled PADS-
Logic and select it with the left mouse
button.  We recommend use of the PADS
Shell.
3)     The PADS-Logic copyright notice and  the
message:
Press any Key to Continue
    will appear.  Press a key and PADS-Logic
system will start.

Should you encounter any problems, call
your local dealer or in the U.S.A., call
our Technical Support Hot Line at (508)
486-3328.



USING PADS-LOGIC


This chapter will get you started by
acquainting you with the graphical user
interface (GUI) and the basic operation of
PADS-Logic.

The Graphical User Interface

When you start the program, the GUI is
loaded, which divides the screen into 4
parts, and a D-size drawing sheet is
displayed. The four areas on the screen are
the Working Area, the System Information
Window, the Command Menu, and the Prompt
Line.

The Working Area is the major portion of
the graphic screen, currently black, where
the D-size drawing is displayed.

The System Information Window is in the
upper left of the screen.  The System
Information Window displays the following
information (from the top):
o    Cursor Position    The  X  and  Y position
of the cursor with
respect to the system
origin (0,0)
o    Drawing Name    The name of the schematic
currently in memory
o    Sheet X/Y    The current sheet , X,
and the total number of
sheets, Y
o    Grid XXX    The user grid in
thousands of an inch.
o    "Postage Stamp"     Locates the viewing
window
    Window    within a current
drawing.  The white
outline is the outline of
the drawing sheet, and
the red area is the area
currently displayed
o    Menu Path    This  multi-line window
lists the current menu
path

Below the System Information Window  is the
Command Menu. This displays  the command
options available in the current menu.

Below the Working Area is the Prompt Line.
This is the primary means of communication
between you and PADS-Logic.

Menu Organization and Command Selection

PADS-Logic  uses  a  hierarchical  command
menu  structure, which starts with a main
menu and has a series of sub-menus
organized for efficient operation.   When a
sub-menu is selected from the main menu,
the  name  of  that  menu  is displayed in
the System Information Window just above
the menu commands.  The command options
associated with the sub-menu will  appear
in  the Command Window, replacing the
commands of the main menu.  Menu commands
are hierarchical, so there may be
additional command options beneath a sub-
menu command.

Commands are selected by either using  the
function keys F1 through F10 located on
your keyboard,  or with your mouse.  The
numbers to the left of the commands
correspond to the  function key numbers,
and  F10 always represents the EXIT
command. To select commands with the
function key, simply select the
corresponding number key.

To select commands with the mouse, move the
cursor over the command option and select
it with the left mouse button. When a 3-
button mouse is available, menu items can
be selected with the middle button by
holding down this button and moving the
mouse. As the mouse is moved, the highlight
bar will scroll through the menu options.
When the left button is pressed, the
highlighted menu command is selected and
the cursor returns to its position in the
working area. The right mouse button always
is used to select the EXIT command.

Loading A Schematic Circuit File

Schematic designs, or "jobs",  are stored
on your hard disk as individual DOS files
with the extension .SCH.  To work on a
design, you must first load the file from
the  hard disk into memory, as follows:
1)     Select the IN/OUT menu (F1) from the
main menu.  The commands for the new
menu will appear in the Command Window.
2)     Select the JOB IN command (F1).  The
prompt line at the bottom of the screen
will request you to input a file name.
3)     Type:
    * <CR>
    A pop-up directory lists the names of
the job files supplied with the
evaluation.
4)     Place the cursor over the name 1STLOOK
in the pop up menu, and press the left
mouse button to bring the design file
named 1STLOOK into memory.  This is a 2
sheet schematic which you will use to
explore PADS-Logic.
    Alternately, in response to the request
to input a file name, you could have
typed:
1STLOOK <CR>
    at the prompt line to bring the file
into memory.

Storing Your Job to the Disk

Designing a complex circuit will take you
some time.  You should periodically save
the design onto the disk as a file. To
store the design on disk, follow these
steps:
1)     Select the In/Out menu (F1).
2)     Select Job Out (F2). You are requested
to give a file name with the message:
Schematic output file name (CR=LOGIC.SCH):
3)     You should use a unique file name. Type
this name followed by <CR>. If this file
already exists, you will be asked to
overwrite it.  Your design job is stored
in a few seconds on the disk, while the
Working  indicator is displayed.

Windowing Commands

PADS-Logic provides a complete set of
window control commands, based on the
numeric keyboard located to the right  of
the main keyboard.  (Note: Your keyboard
must have NUM LOCK turned off in order  to
access the Windowing Keys.) The function of
each key is as follows:

Num 1 / End: Redraw the screen
Num 2 / down arrow: Move the window down
Num 3 / Pg Dn: Zoom out
Num 4 / left arrow: Move the window left
Num 6 / right arrow: Move the window right
Num 7 / Home: Show the entire board
Num 8 / up arrow: Move the window up
Num 9 / Pg Up: Zoom in
Num 0 / Ins:  Reposition window with cursor
in center
Num  . / Del: Create a window zoom box, and
you will define the limits of the box

Remember that the Postage Stamp indicates
the position of the viewing window relative
to the schematic.

Automatic Panning

When you reach the edge of the graphic
screen, PADS-Logic will automatically pan
the graphic screen to let you continue
working. This is called automatic panning.

The parameters for panning are controllable
by you, using the SetUp command. These
parameters allow you to define the
sensitivity for panning and your desired
panning distance. You control them as
follows:
1)     From the main menu, select SetUp menu
(F8)
2)     The options of the SetUp menu are
displayed. Select Parameters (F2).
3)     A new display, with the system
parameters, is shown.
    Four of these control panning: Pan
Enable lets you turn the panning on or
off with "Y" or "N". Pan Sensitivity
defines how close to the edge of the
working area you need to be to start the
pan. Pan Delay defines how long the
software should wait when your cursor is
at the edge of the screen before
panning, and Pan Distance defines how
much the window should be moved, as a
percentage of the whole Working Area.
    To modify a parameter, select the value
to the right of the parameter with the
mouse, and type a new value.
4)     When you are finished, select  Exit
(F10).

Assigning Colors to Items

PADS-Logic uses a 16 color palette to let
you change any item in the schematic to a
color of your choice. This is also done in
the SetUp menu, as follows;
1)     When you enter the SetUp (F8) routine,
the schematic disappears and is replaced
by a color selection menu. The top row
is the palette of colors. Below this are
listed items in the schematic: PARTS,
TEXT, BUSES, etc. Some of these are
surrounded by colored boxes. These boxes
represent the current color of the
items.
2)     To choose the desired color, move the
cursor on top of the color and select
with the left mouse button or F1.
3)     Select the item whose color you wish to
change with the mouse. A highlight box
of the color selected will surround the
item, indicating that its color has
changed. To make an item invisible, set
it to black, the background color.
4)     When you are zoomed far out and text is
very small, it will disappear. You may
choose to see a rectangular box around
the text, by making the "Box" visible.
5)     When you select Exit (F10), the design
reappears with the assigned colors.

Modeless Commands

Modeless commands save you time. They let
you select commands without going through
the menu hierarchy. For example, you can
instantly search for a part across your
entire circuit, switch between sheets in
your design, or change text height and
width.

The following lists all of the time-saving
modeless commands that are available to you
in PADS-LOGIC.
Sxxx    Search  for an item.  xxx can
be  a part,  a signal name, or
an x/y coordinate.
Q    Start the query function.
After selecting, position the
cursor over a part or a signal
and select it with the left
mouse button.
SHx    Change to sheet x.
T xxx yyy    Changes current text height and
width.
W xxx    Changes the current line width
to xxx.
C    Select either the standard or
full screen cursor.
Gx    Changes the current system grid
to x mils. The minimum grid is
2.
HI    Move down or into a
hierarchical symbol.
HO    Move up the hierarchy or out of
a hierarchical symbol.
Ctrl PgDn    Dimensioning aid, shows
relative cursor movement.
Alt-9    Displays a  file in a pop-up
window.
Alt-0    Displays error messages from
PADS-Logic.
Zx    Zoom by a factor of x.  Zoom
factors are:
       1 = 64" complete database
(64" x 64")
       2 = 32"
       3 = 21-23", etc.
Arrow Keys    Moves cursor 1 grid in the
requested direction. These
arrows are the separate arrow
keys, not the arrow keys on the
numeric keypad.

Three of these commands require further
explanation, as you will use them often.

Selecting a Sheet in the Drawing
There are  two sheets in the 1STLOOK
circuit, and you can switch between them
very quickly using the SH modeless command:
1)     To move to sheet 2, type:
SH2<CR>
    to select sheet 2
2)     To go back to sheet 1, type:
SH1<CR>
    to select sheet 1

Using the Search Command
The Search command will let you search for
a part or other item in the circuit. Since
the Multi-Sheet Database holds all of the
schematic data in memory, you can
immediately access any item in the database
on any page of your schematic!
1)     To illustrate this, while viewing sheet
2, enter:
    SU19 <CR>
    to search for a part named U19.
2)     PADS-Logic has the intelligence to
switch back to sheet 1, and
automatically highlight the part. This
is an inverter symbol.  In the System
Information Window,  is displayed
information about the selected gate.
The first gate is U19A.
3)     You select Next (F1) to find the next
gate in U19, U19B.
4)     Keep selecting Next (F1) until all 6
gates in U19 have been highlighted.

Signals can be located just as easy.
1)     Search for a signal named "21" by
typing:
    S21 <CR>
2)     PADS-Logic will find the correct sheet,
place the cursor over a pin in the
signal, and give information about the
pin in the System Information Window.
3)     The cursor will jump to the next
instance of the signal when Next (F1) is
selected.


The Query Command
The Query command enables you to find out
information about any component or signal
in the database.
1)     To use the Query command, type:
    Q<CR>
2)     Select the outline of a component to be
queried with your mouse.  A pop-up
window containing a list of each pin in
the part  is displayed, along with the
pin type, its signal name and its sheet
location.
3)     You remove the pop-up window by pressing
Esc.
4)     When you query a signal connection, the
pop-up window will display all the
components and pins in the signal, along
with the sheet location and pin type for
each pin.
5)     Select Abort (F10) to exit the Query
command.

Reviewing the Job Limits

The Shareware version of PADS-Logic is
fully functioning, but the maximum design
size has been limited in two ways. First,
the maximum number of sheets supported of
any size is two sheets, rather than the 256
sheet limit of the actual PADS-Logic
program.

Secondly, the maximum number of parts,
connections, gates, and so forth is also
limited. The limit allows you to do a
design with a complexity of  approximately
30 IC's, but the total varies depending on
the type of design, number of connections,
and other parameters. If you are doing a
design that approached this limit, you
should check how close to the system limits
you are. This is done as follows:
1)     Select the In/Out menu.
2)     Select Reports (F7), then select Job
Limits (F7).
3)     You area asked to give the name of a
file to which the limits are stored.
Type:
LIMITS<CR>
4)     The limits report file you created is
displayed in the pop-up window.
5)     For each data type in the circuit, you
will see the current number used and the
maximum number available. If you reach
the maximum number, the software will
prevent you from assigning any more
items.



CREATING A SCHEMATIC


Now that you are familiar with the basic
commands in PADS-Logic, you are ready to
start designing a circuit. This chapter
explains how to add parts and connections
through a series of exercises. Throughout
the evaluation, you will be working with
the schematics named PARTIAL and BUS.
1)     To begin, load the schematic named
PARTIAL into PADS-Logic. Select In/Out
(F1) from  the main menu, then select
Job In (F1).
2)     The prompt line asks the following:
Job already in memory.  OK to overwrite with new
input job (Y/N)?
3)     Select Y or function key F1 for YES,
and type:
PARTIAL <CR>
4)     The circuit is loaded into memory.

Adding Parts to a Schematic

When parts are added to a PADS-Logic
schematic, they are automatically assigned a
reference designator name  (and gate number
if appropriate), and pin numbers. PADS-
Logic knows how many gates are in each
part, and will assign them as well. This
saves considerable time that you would
otherwise spend in manually adding text to
the circuit. It also insures that no
duplicate names are in the circuit.

During placement, you may want to change
the cursor to a full screen cursor to aid
in your placement of the component.  This
is done by typing:
C<CR>

Adding a Part From the Library
Parts can be added to the design from the
library very easily. To add  a 1/8 watt
resistor to the circuit, proceed as
follows:
1)     From the main menu, select Add Part
(F2).
2)     At the prompt line, type in:
    R* <CR>
    (The symbol * is used as a wild card to
enable you to browse through the PADS-
Logic library. )
3)     The library browse command provides an
easy method to scan a list of components
visually.  A pop-up window is presented.
The bottom half shows a list of parts
corresponding to your wild card command,
in this case all parts beginning with R.
The top half shows the symbol for the
currently highlighted part.  You can use
the arrow keys to scroll through the
list of components, or you can place the
cursor over a part type and press Select
(F1) to view the specific graphical
symbols.
4)     To add the 1/8 Watt resistor, place the
mouse cursor over STD: R1/8W, choose
Select (F1), then Accept (F2). The pop-
up window disappears and the resistor
will be attached to the cursor.
5)     Move the cursor around and notice how
the part follows. Set the resistor in
place with Complete (F1). Notice the
system has assigned a reference name to
this resistor, R1,  with no effort on
your part, and another resistor part is
immediately available on the cursor.
6)     Select Alternate (F5) to view the
different symbols in the library that
are  available to represent this part.
Toggle the Alternate (F5) command to the
original resistor package and select
Complete (F1) to finalize the placement
of R2.
7)     Select Exit (F10) or the right mouse
button to stop adding resistors.

The text entry "???" below the resistor is
reserved for the location of the resistance
value of the component.  We will
demonstrate the simplicity of entering a
value for each  resistor in the Changing
Part Attributes section of this evaluation.

Adding a TTL part from the library
Adding a 74HC193 gate is done similarly.
1)     Select ADD PART (F2).
2)     At the prompt line, type in:
    \193 <CR>
    This means to display all of the parts
that correspond to the "XX193" logic
group, e.g. 74193, 74LS193, 74F193, etc.
Move the highlight bar over 74HC193 and
ACCEPT (F2), and the part is added to
the cursor  and is ready for placement.
3)     Investigate the effect of the following
commands:
    - ROTATE (F2)  to rotate the part 90
degrees.
    - MIRROR X (F3) to mirror the part in
the x axis.
    - MIRROR Y (F4) to mirror the part in
the Y axis.
4)     Set the part with Complete (F1). A
second symbol attaches to the cursor.
Place it as well, and note that the
reference name and pin numbers are
automatically assigned.
5)     Select Exit (F10) to escape from the
part addition sequence.
    Alternately, you could have typed:
    74HC193 <CR>
    and the part would have been copied
directly from the library. In either
case, note that the component is
assigned a reference name and is given a
gate number.

Adding a Part with the  Copy Command
Parts can be added to the schematic without
going to the library if they already are in
the schematic, using the COPY command.
1)     Place your cursor over one of the
symbols just added and select Copy (F5).
2)     PADS-Logic will copy the part symbol,
attach the copy to your cursor for
placement,  assign a name and pin
numbers to the part, and increment the
reference designator name  to the next
available name.
3)     Place the symbol with Complete (F1).

You now have an appreciation of how to add
parts to a schematic utilizing the add part
command with library browsing, or using the
copy command when a sample of the part is
already on your schematic.

Editing Text in the Schematic

The Edit Text command is a powerful command
that allows you to modify text entries in
the circuit.  It  enables you to change
reference designators, component part type
names, signal names, bus names, part values
and tolerances, and pin numbers. You should
become familiar with all of the functions
of this command.

Changing the Part Name
Parts in PADS-Logic have a number of part
attributes: part type, price, manufacturer,
etc. It is possible to change the part
attributes associated with part U3A as
follows:
1)     If you do not see U3A, type:
SU3A
    to center it in the Working Area. Select
Exit F10 to stop the search process.
2)     Place your cursor over the reference
name for U3A and select EDIT TEXT (F4).
3)     A pop-up window is presented  with the
REF NAME highlighted in Blue.  This pop-
up window contains all of the attributes
associated with the part U3A. The REF
NAME is presented at the prompt line,
ready to be changed.  Use the backspace
key to delete the old name, and type a
new reference designator name,  as
follows, and watch what happens:
U2A<CR>
4)     A message appears stating:
Component name is already used by a part with a
different part type
    The name change will not occur, because
you have selected an existing name.
PADS-Logic insures you NEVER have to
worry about duplicating reference
designators!
5)     Select a new name, U50, by entering:
U50A <CR>
    at the prompt line.  Select Exit (F10)
to see the change.

Changing a Part Type
You may also want to change the part type
associated with a part. To do this:
1)      Position the cursor over gate U2D
located just above gate U50A, and select
the  Edit Text (F4) command.  (The
cursor should be on the symbol outline).
2)     A pop up window with the symbol
attributes appears. Select the Part Type
attribute, and it will appear on the
prompt line. Type in the new part type
name at the prompt line:
74LS04<CR>
3)     When a new part type is entered, the
menu changes to give you 3 options.
    o This Gate will change only the
selected gate to the new part.
    o This Part will change all of the
gates in this part to the new part name.
    o All Parts will change all parts of the
same type to the new part type.
    Select This Gate (F1), and Exit (F10)
4)     The part type is now changed, as is the
reference name. The reference name
changes because the gate can no longer
be part of the same package as the other
7404 symbols, so it is assigned a new
package and a new reference  designator
name.

Making a Pin Swap
PADS-Logic  has  the  ability  to
automatically  swap  pins  within a gate
without  making  changes  to  the  gate  in
your  library!   This feature enables  you
to rearrange the pins on an individual part
to  make the  flow  of  the  schematic
more pleasing. The swapping of pins must
occur before you add connections.

Using Edit Text (F4), select  the LD pin on
one of the 74HC193 symbols that you added.
The prompt line requests you to select a
pin to swap with your original pin number.
Place your cursor over the CLR pin and
press the left mouse button.  The LD and
CLR pins are instantly swapped, including
all information with them.

Adding Parameters to a Part
You can use the Edit Text (F4) command to
customize your schematic to include new
parameters in a part without accessing the
library!  For example, let's add a company
stock number parameter to the 74HC193 in
the circuit.

1)     Place your cursor over the outline of
the part and select Edit Text (F4), then
select Add Item (F2).
2)     At the prompt line, type in your new
parameter name >
Company Stock # : <CR>
3)     The new parameter will now be added to
either This Part (F1) or All Parts (F2).
Select All Parts (F2).
4)     The prompt line then requests your input
for its value.  Type in your desired
Company Stock number, for example:
145678
5)     The new value will now be added to
either This Part (F1) or All Parts (F2).
Select All Parts (F2).
6)     Place your cursor over OFF, highlighted
in blue, and select it with F1. The
visibility will change to ON.
7)     Select All Parts (F2), and Exit (F10) to
display your company stock number on all
of the 74HC193 gates.

Adding Connections

Adding signal connections with PADS-Logic
is quick and easy. Connections can be added
the following ways:
o To a pin of a part
o To another connection
o To a data bus
o To an off-page tag
o To a ground or power symbol

Unlike other schematic systems that use
general 2-D graphics data, PADS-Logic's
intelligent database will not allow you to
leave a connection hanging anywhere in the
database. Because of PADS-Logic's self-
checking database, the connection must be
connected to one of the  items above. This
eliminates the need for time-consuming
post-design error correction that results
from allowing a connection to start or end
anywhere in the drawing. To make a
connection:
1)     Place your cursor over the item (pin or
other connection) from which the new
connection is to originate, and select
ADD CONN (F3).
2)     Drag the cursor in the desired
direction. A white connection will
follow the cursor movement.
3)     Press the left mouse button each time
you want to add a corner.
4)     To finish the connection, place the
cursor over a legal end point as defined
above and Select  (F1) once again.  The
connection will change color, indicating
it is entered in the design.
    When starting or finishing on a
connection,  PADS-Logic  will
automatically  insert  a tie dot at the
junction.  You do  not need to worry
about adding tie dots later, as with
other schematic packages.  Try this.

Adding a New Sheet to the Design

We said earlier that PADS-Logic uses a
Multi-Sheet Database; now you will see the
power of this. First, you must add a second
sheet to this circuit. This is done as
follows:
1)     From the main menu, select In/Out (F1).
2)     From the In/Out menu, select Sheets
(F5). A new sub-menu is presented.
3)     Select Add Sheet (F2). At the prompt
line, the message:
OK to add sheet 2 (Y/N)?
    Respond with F1 to add the sheet. The
current drawing is replaced by an empty
schematic drawing, and the message in
the System Information Window is Sheet
2/2.

Adding Off Page Tags to a Connection

Sheet tags, or off page signal tags, are
used to connect two or more connections
with the same signal name together on one
or more different sheets of the schematic.
1)     Add a 74LS174 component to the second
sheet of the circuit by selecting Add
Part (F2) and typing:
74LS174 <CR>
2)     Start a connection from one of the new
component's input pins with the Add Conn
(F3) command, and extend it about one
inch to the left.
3)     Select  Off Page (F4) to add the off
page symbol.  You can rotate, mirror, or
select an alternate off page symbol if
desired. Select Complete (F1)  to
position the symbol.
4)     To the prompt, type the net name for the
off- page signal:
ADDR1<CR>
5)     If you wish to move the sheet tag name,
use Move  (F2), then Complete (F1) twice
for final placement.
6)     Now, go to sheet 1 of the circuit and
add a connection ending with  an off
page tag, and assign the same signal
name, ADDR1.
7)     When you query this signal with the Q
command, you will see that it is
connected to the signal on sheet 2 of
the circuit!

Adding Power and Ground Symbols

If  you take  a close  look at this
schematic, you will notice there are no
power  and  ground  connections  for  most
of  the components. PADS-Logic
automatically keeps track of the standard
power  (+5V) and  ground  pins  for  the
parts in  the library, you don't have to!
    You will also need to know how to add
power and ground signals to signal pins.
1)     Select sheet two by typing:
SH2 <CR>
    You will add a ground pin to one of the
inputs on the 74LS174 symbol.
2)     Select Add Conn (F3) and point at an
input pin. Move the cursor to the left 1
inch, and the connection follows.
3)     At an appropriate place to add the
ground symbol, select Ground (F5).
4)     Use  Alternate (F3) to view the
available symbols.  Observe that as you
toggle through  the ground symbols, the
net name displayed in the System
Information Window  changes between GND,
AGND and CHGND, indicating different net
names. You  can create your own power
and ground symbols,  each  with  their
own  net  names.
5)     Select the AGND signal and complete the
connection with Complete (F1).

Adding Net Names to a Signal

PADS-Logic automatically assigns net names
or signal names to all connections in the
schematic as a connection is added. These
net names begin $$$xxx, and are generally
not displayed in the schematic.  You may
wish to assign your own names instead.
1)     Place your cursor on a segment of a
connection that is attached to a pin,
and select Edit Text (F4).
2)     The Prompt Line displays the current
name.  Type in a new net name at the
prompt line, for example
NEWSIG <CR>.
3)     Use Move (F2) to locate the signal name.
4)     Select Complete (F1) twice for final
placement.

Adding a Bus

Creating a bus requires placing a new type
of data element and connecting to it with
connections. This exercise adds a bus on
sheet two of the circuit.
1)     To begin this exercise, load the
schematic named BUS into PADS-Logic.
Select In/Out (F1) from the main menu,
then select Job In (F1).
2)    Type:
BUS <CR>
    at the prompt line.
3)    Using the Copy (F5) command, copy
component U3, part type 6167.
4)    Place the new component U4 about 1.5" to
the right of U3.  The full screen cursor
may be helpful lining up the component
with the other 6167 components.
5)    Exit the Copy command.
6)     Zoom in with the PgUp key. Select  the
Other Menu (F9) command. The first
command in this new menu is Add Bus.
7)     To start the bus, move the cursor to the
location about 1" left and 1/2" above
pin 11 of your 6167 (U4). Select Add Bus
(F1) and create the bus line by dragging
the cursor down below the part.  Overlap
the Bus Line in the same manner as the
bus line for U2 and U3, then  select
Complete (F9).  The bus  line will turn
blue, indicating the placement is
finalized.
8)     You will be prompted for the bus name in
the following format:
(Format = xxxx[nn:mm] )>
    Type in the bus name:
ADDR[00:13] <CR>
9)     The bus name appears. Select  the Move
(F2) command to position the bus name as
desired, and select Complete (F1) to fix
the name. Select F1 again to complete
the bus.

Adding Connections to a Bus
You are now ready to add the connections to
the bus. This is done using the Add Conn
(F3) command from the main menu.
1)     Start the connection at  pin 1 of your
6167.
2)     Drag the cursor to the bus and complete
the connection on the bus line with
Crn/Finish (F1).
3)     The first net name in the bus is
displayed at the prompt line, ADDR00.
4)     Use Move (F2) to relocate the name and
select Complete (F1) twice for final
placement.
5)     Add  3 more connections to the bus from
pins 2, 3, and 4. Note that the bus-name
bit numbers increment each  time you add
a new connection.

A repetitive function like adding multiple
connections to a bus   is often made easier
if you use PADS-Logic's macro language.
This is not described in this manual, but
is fully explained in the PADS-Logic
Reference Manual.



Edit Commands


This chapter demonstrates the use of the
editing commands in PADS-Logic. These
include the Move and Delete commands. One
of the advantages of PADS-Logic is that
these commands are context sensitive. This
means that  a command senses the type  of
data  selected, and PADS-Logic responds
with  the  appropriate  operation depending
on the type of data.  The advantage of this
for you is that PADS-Logic  can  have  a
very  simple menu structure, with  all
editing commands  in the main menu and
accessible with one key.

The Move Command

The Move  command is used to move:  parts
and gates, part text, connection segments,
connection end points, connection tie dots,
hierarchical symbols, text, 2-D lines,
unconnected data buses, net names, and off-
page references. The Move command is so
simple to use, it needs no explanation -
simply place the cursor on the item  and
select Move. When you move a connected
part, the connections remain attached to
the part. Also, if you move a middle
segment in a connection, it stays connected
as well. You cannot accidentally lose
connectivity with PADS-Logic.

If you want to move a connection to another
pin, this can be done by selecting and
moving the last segment connected to the
pin. The connection will attach to the
cursor,  and is free to be connected to any
other pin or connection.

The Delete Command

The Delete command is used to delete  items
in the circuit. It is also context
sensitive, so you use this single command
to delete parts, connections, text items,
etc.  Try the following:
1)     Select sheet 1, place the cursor over a
part and select Delete (F7) from the
main menu.
2)     The system recognizes the item and
erases the part from the screen and  the
prompt line then asks you to confirm the
Deletion.  Responding   "Y"   or F1 will
complete the deletion.  The component
and  any connections to it, will be
deleted. If you respond  with "N" or
F10, the deletion is cancelled and the
part reappears.

The Copy Command

This command is used to copy parts, 2-D
line items, and free text. You cannot use
it to copy connections, busses, off-page
tags, etc.

Working with Groups

The Group command  can be used to
manipulate  a group of parts  with a single
command. Once  a  group  is defined,  it
can be moved,  rotated,  deleted,
mirrored,  copied, and saved to  the hard
disk  for  use in another design.  To
illustrate  the group  operations,  do the
following
1)     From  the  main  menu,  select Other
Menu (F9),  then Group command (F4).
2)     You will create a box window of the
items to be captured as a group.  Place
your cursor at the lower left of the
items to be grouped and select the
Define Group (F1) command.
3)     Drag the cursor to the upper right
corner and select Complete (F1) to
enclose the group area.  The group will
be highlighted and the menu will change
to allow you to manipulate the group.
4)     Add Item (F8)and Delete Item (F9) can be
used to add additional items or delete
items from the group.  Move Grp (F1) and
Copy Grp (F2) can be used to move or
copy your group anywhere on the current
sheet.

Group Cut and Paste
A group may be "cut out" of the design,
saved as a file and "pasted" in another
sheet of the schematic or used in another
design.  To demonstrate this powerful
feature:
1)     Select Cut Grp (F4).  Enter the File
Name:
 GRP1
    at the prompt line. Respond to the next
prompt:
Cut connections at boundary (Y/N)?
    With F1 or Y. The group is now saved to
your hard disk in the file GRP1.GRP.
2)     Exit (F10) from the Group command and
select sheet 2.  This is where you will
paste the group
3)     Select the Paste Grp (F2).  Enter the
file name of the group to be pasted at
the prompt line:
GRP1<CR>
    A box outline of the group is placed at
the cursor.  Position the group in your
desired location, then select Complete
(F1),  and Exit (F10), and the parts are
displayed. PADS-Logic automatically
assigned new reference designators to
the parts in the new group.



Reports and Drawings


PADS-Logic offers a complete set of outputs
for producing net lists in a variety of
formats, creating reports, and producing
drawings of your circuits. This chapter
will explain how to produce a PADS-PCB
netlist, a pen plot drawing, and how to
produce  a bill of material listing. The
other reports and outputs can also be
examined at your convenience.

Creating a PADS-PCB Netlist

Once the schematic is complete, you can
create an output netlist of the circuit in
a variety of formats. These netlists can be
used as inputs to a PCB CAD program, or for
simulators. To create a PADS-PCB net list,
do the following:
1)     Select In/Out (F1) from the main menu.
2)     Select Reports (F7), then Netlist (F1).
3)     The available netlist formats are
displayed. Select PADS-PCB with the
cursor. You will be prompted for the
name of the file to create:
Netlist output file name (CR=report)
    Type a file name, followed by <CR>, for
example
NET1<CR>
4)     The system will be busy for some time
while the file is created. When it is
finished, the Busy message is removed.
5)     The file you created can be displayed by
typing Alt-9 (while depressing the Alt
key, select 9). The message:
File name (CR=):
    appears on the prompt line. Type the
name of the file
NET1<CR>
    and it is displayed in a pop-up window.
    Note, any text file can be displayed
with the Alt-9 command.
6)     Net lists for other CAD systems and
simulators are created similarly.

Making a Bill of Materials Report

The Bill of Material (BOM) report provides
a listing of the parts contained in the
schematic along with user selected
attributes.  This command can extract any
part attribute that has been assigned to a
part in the schematic or in the library.
Customizing the format is easy, so you can
produce the report in any way you desire.
1)     From  the  main  menu,  select  In/Out
(F1), then  Reports (F7), then  select
Bill Mat (F2).
2)     You will be prompted for the name of
bill of materials file name.   Enter the
filename at the prompt line:
BOMTEST<CR>
3)     You will be prompted for a format name.
Accept the default format by entering a
<CR>  . PADS-Logic lets you define a
number of different reports and save
them to disk.
4)     At this point you can modify the report
to your desired format.  You can define
the attribute to be listed, the position
of the field in the report (by adjusting
the start and end columns) and the title
for the field. You can also define the
attribute which you want the report
sorted on.
5)     Select Complete (F9) when you have
finished defining the format, the report
is saved to disk and can be printed.
6)     To view the report , select ALT-9 and
type:
BOMTEST
    at the prompt.  The report will appear
in a pop-up window. Be aware that the
number of columns on the screen is less
than your printer's capability, so some
overlap may occur.

Producing a Pen Plot

PADS-Logic can produce drawings in formats
that are compatible with most dot-matrix
printers, Postscript and HP laser printers,
HP and Houston Instrument pen plotters, and
Gerber photoplotters. You define the
plotting devices that you have during the
installation process.

The procedure to produce a drawing is
similar, no matter which type of output
device you are using. The following
procedure is for a pen plotter:
1)     From the main menu, select In/Out (F1),
then Plot (F8).
2)     Select Penplot (F3). A pop up window
with a number of options is displayed.
You will select the appropriate option
settings to initiate the plotting.
Selection is done with the mouse.
3)     You first select the Sheets to Plot
option. The choices are toggled each
time you select with the mouse. They
are: Current Sheet, All Sheets, Numbered
Sheets, or Hierarchy. Select Current
Sheet.
4)     Next, you define whether the plotter is
on-line (i.e connected to your PC and
currently powered on). If not, select
off-line.
5)     You may choose to print the job name for
the plot.
6)     You may select to plot the entire sheet
or just the visible window. Generally
you would select the entire sheet.
7)     The next option,  Location,  defines the
location of the schematic on the drawing
sheet. If this is a check plot, the best
choice is Scale-to-fit or Centered. You
can also define the margin or the
offset, but this will require some
practice.
8)     The next four options: Rotation, Scaling
Ratio, Horizontal Offset and Vertical
Offset, are used to adjust the position
of the drawing on the paper, if you did
not select  "Scale-to-Fit" or
"Centered".
9)     Plotter pen width defines the width of
the pen, so the program knows how many
lines are required to fill a solid
object.
10) If you are plotting "off-line", you
will be creating a file, and the name is
supplied for Off-line Plot Filename.
11) When all answers are correct, select
Complete (F9) to proceed.
12) If the plotter is on-line, the program
will drive the plotter to produce the
plot immediately. Otherwise, a file is
created in HP format for later plotting.




LIBRARY PART CREATION


PADS-Logic comes with an extensive parts
library of over 6000 parts, so you can
immediately begin to draw a wide range of
circuits.  However, as every experienced
schematic software user knows, creating new
library parts is an inevitable part of
using any  system.  Therefore, component
creation should be an essential determinant
in your evaluation of a system.

PADS-Logic contains an integrated
graphical parts library editor for creating
new parts.  To get an appreciation of  the
ease of component creation with PADS-Logic,
you will have the opportunity in this
exercise to construct two  parts using
PADS-Logic's graphical part editor.
Creating a library part is a two-step
process. First, the electrical information
for the part is created, then the actual
schematic  symbol is defined.

Creating an Integrated Circuit

In this exercise , you will create a
digital  component, by creating a part, the
Am27C256, which is a 32K x 8 bit EPROM
manufactured by AMD.  This is a 28 pin IC,
with the following pins:
A0-A14 address inputs: pins
10,9,8,7,6,5,4,3,25,24,21,23,2, 26 ,27
CE and OE enables: pins 20, 22
DQ0-DQ7 data in/out: pins
11,12,13,15,16,17,18,19
VCC pin 28
VPP pin 1
GND pin 14

Creating parts of this type is very easy
using the automatic part creation function
in PADS-Logic
1)     Select The Other Menu (F9) from the main
menu. Then select Hier/Lib (F9). From
this menu you can create or edit all
symbols used in PADS-Logic. (You can
also use the macro command Alt-L to
enter the library editor.)
2)     Select Part Type (F1).
3)     In  response  to the  message at the
prompt line, type:
AM27C256<CR>
    The schematic is saved, the graphic part
editor  is entered, and the message:
Part  AM27C256 does not exist. Create part? (Y/N)>
4)     Select Y to start the creation process.
A new menu is presented, allowing you to
define the electrical information or
modify the gate.
5)     You should complete the electrical data
first.  Select Electrical (F1).  This
defines the PCB symbol, the text
attributes that are displayed on the
schematic or extracted for reports, the
default power and ground pins, etc.
6)     The electrical text screen will be
presented and you proceed to fill in all
the data necessary.
    o There is no part type prefix, so this
line may be left blank.
    o The Logic Family  defines the  family
with which the part is associated, i.e.,
TTL, CMOS, ANA (for Analog), etc.  Since
this is a CMOS part, enter CMO.
    o The PCB Decal entry defines the name
of the physical shape that will be used
for the part in the circuit board. Since
this is a 28-pin DIP IC,  enter:
DIP28\400
    o Part Attributes. You may assign any
type of attribute to a part.  Allocate 2
attribute lines and enter in the
information below in the two lines. All
lines start with an attribute name,
followed by a colon (:), followed by the
attribute data.
    PART DESC: 32K x 8 bit EPROM
    MFG #1: AMD
    You may want to add new attributes such
as  "Vertical Height," which may be
useful for mechanical packaging or
thermal analysis. Discrete parts would
also have a "value" attribute and a
"tolerance" attribute.
    o The Displayed Attribute Lines entry
lets you define the attributes to be
displayed when the schematic is drawn.
In this case, none will be displayed, so
leave the entry blank.
    o The Non-Numeric Pin Number entry lets
you define a  part with pin names rather
than numbers. As this part  uses pin
numbers, leave this entry as N (No).
    o The Number of Signal Pins entry is
used to define  standard power and
ground pins in the part. PADS-Logic will
automatically add these pins to the
power and ground netlists when you add
the part to the schematic.  The Am27C256
has 3 standard signal pins,  VPP (pin
1), GND (pin 14), and +5V (pin 28),
therefore, enter:
3
    o PADS-Logic requests the pin number,
signal name, and its PCB track width.
    On the first line, enter the pin number
as 1, the signal name as VPP, and the
track width as 50.
    On the second line, enter:
14    GND    50
    On the third line, enter:
28    +5V    50
    o The Number of Gates parameter
indicates the number of gates in the
part, with 1 as the default.
    o The Gate Type defines whether each
gate is swappable in the PC  board.  A 0
indicates "no swapping allowed" a 1
indicates the gate may be swapped with
the same package or other packages of
the same part type. The 0 default value
can be left as it is.
    o The Gate Decal and Alternate
information is used to identify the
symbol for  the part in a schematic.  Up
to 3 alternate decals, including
DeMorgan equivalents, can be specified
for each part. The default symbol name
is AM27C256.
8)     When you finish entering the electrical
information, select Complete (F9).

Creating  the  Symbol

After defining the parameters for the part,
the next step to complete the part creation
is to edit the symbol.
1)     Select  Mod Gate (F2).
2)     Since this symbol, AM27C256, does not
exist, a message asks if you want to
create the box symbol automatically.
Respond with Y.
3)     The prompt changes to:
Number of input pins and output pins>
    asking you to define the number of pins
in the part. This part has 25 pins that
will appear in the circuit (plus the 3
standard voltage pins), with 17 inputs
and 8 outputs. Type:
17  8 <CR>
4)     You must then define the type of pin to
use for the inputs and outputs. Respond
to the prompt:
Select Pin decal for input pins
    by selecting the name PIN in the pop-up
window with your mouse. Repeat for the
output pins.
5)     The part is automatically created, with
17 input pins on the left side and 8
output pins on the right side. You must
assign pin numbers and pin names to
these pins.
6)     Select Terminals (F3) and Set PName (F5)
The message:
Enter Pin Name>
    appears, and you should type the first
name:
A0<CR>
7)     Place the cursor over the first input
pin and select it. The pin name is
assigned to be A0. Then, select the
second input pin with the mouse, and it
is assigned to be A1 automatically,
because the name is incremented.
Continue through A14.
8)     Exit, and reselect Set PName (F5). To
the prompt, respond:
\CE<CR>
    and select one of the remaining unnamed
inputs. Note that the name that appears
is not \CE but CE with a bar. Preceding
the name with the \ character will
create a bar over the name.
9)     Name the last input \OE, and the 8
outputs DQ0 through DQ7.
10) Exit and select  Set PNum (F4), to
assign the pin numbers , based on the
assignments listed above. Since  pin
numbers also automatically increment
each time you use one, the best way is
to start with pin number 2, by typing
2<CR>. This is the pin number of input
A12, which is the thirteenth input pin.
When this pin  is selected with the
mouse, the pin number is assigned, and
the next pin number is incremented.
Continue assigning pin numbers until all
are completed. Note that to skip a
number (for example, pin 14), assign pin
14 and then reassign it as pin 15.
11) The next step is to move the part
origin. The origin is the location that
you will pick up when placing the symbol
in the schematic, and is generally set
to the first input pin. To do this,
select Exit (F10), move the cursor on
top of the first input pin, and select
Origin (F8). A white marker is placed on
pin 1.
12) Carefully examine the symbol, making
sure you have entered all the necessary
data. Select Complete (F9) to exit.
13) After completing the electrical and
gate information, you should always run
a check of the part using Check Part
(F8).  Correct any error messages before
you save the part.
14) When the message is "No Errors Found",
use Save Part (F9) to save the part
definition in  the  library.



OTHER COMMANDS


In this short manual, it is impossible to
explain fully all of the powerful commands
in PADS-Logic. We have instead chosen to
highlight those features we think are most
significant and unique: the advantages of
the multi-sheet database, the simplicity of
design that comes from an intelligent
database, and the strength of true system
integration and automatic change control.

Other features that we have not commented
on, but which are well worth exploring are:
the reports available from the software,
the sophisticated PLIB library  manager,
the availability of a wide range of net
lists,  the ASCII interfaces for
communications with other systems, and the
macro command language.

You are free to experiment with the other
commands described below.  If you have
questions, call your local PADS dealer or
our hot-line support team, or order a copy
of the entire user manual.

The ECO Commands

Every circuit  that has ever been designed
has required changes.  As a result, a key
criteria in your CAE/CAD system should be
how well the system handles engineering
changes. PADS-Logic, in conjunction with
PADS-PCB, provides true integrated engineering!  No
matter where you make your engineering
change order (ECO) changes, PADS ECO
functions guarantee that your schematic
will be electrically identical to the
board.  The ECO function is located in the
In/Out menu, and has two options, To PCB
(F1), and From PCB (F2).

To PCB (F1) is used to send a set of
changes made in the schematic to the
circuit board. This list of changes is
calculated by comparing your current
schematic with an existing job file.
Differences are listed as a series of
changes that are stored in an ECO file and
can be used to automatically update the
board. The changes can include: Added
Parts, Deleted Parts, Added Connections,
Deleted Connections, Renamed Nets, Renamed
Parts, and Changed Part Type of Parts.

From PCB  (F2) will read an ECO change file
that is produced in PADS-PCB, and
automatically update the current schematic
with the changes. These changes are limited
to gate and pin swaps, and component name
changes, collectively known as "back-
annotations". To see the effect of this, do
the following:
1)     Load the schematic file RENAME into
memory. This is a small 5 part
schematic.
2)     Select ECO (F6).
3)     Select From PCB (F2). In response to the
prompt for the name of the ECO file,
type:
RENAME.ECO<CR>
4)     Type ERR<CR> as the name of the error
file. If PADS-Logic cannot properly
update the job, this file will hold a
list of errors.
5)     The file will be read, and the schematic
will be updated. Note that all of the
part names have changed.
6)     If you wish to view the ECO file, select
Alt-9, and type:
RENAME.ECO
to the prompt. The ECO file will be
displayed.

Hierarchical Design Commands

Hierarchical schematics are used to support
a  design methodology of top-down or
bottom-up circuit creation. Top-down design
enables you to initially organize your
circuit  as a set of generalized functions,
and then develop each function into more
detailed sub-functions until ultimately
each sub-function is an integrated circuit
or discrete part element. Bottom-up design
is the opposite of this, you start at the
level of individual parts and convert a
group of parts into a functional element.

Each hierarchy in PADS-Logic is a separate
schematic sheet, and because the Evaluation
Package is limited to two sheets, you
cannot work with this capability. The
command to create a hierarchical symbol is
Hier/Lib (F9), from the Other Menu, and
then Hierarchy (F7). Within this command
are the facilities to automatically create
a hierarchical part, assign a sheet to the
part, and navigate the hierarchy. The
commands to navigate, or move up and down,
the hierarchy are HI (move down into the
hierarchy), and HO (move up out of the
hierarchy).

ASCII File Commands

PADS-Logic provides a totally open
database, through its ASCII file commands.
Users who wish to do so may convert a PADS-
Logic schematic to another CAE or CAD
system by first outputting the circuit as
an ASCII file with the ASCII Out command.
Similarly, the ASCII In command will
convert a text file in PADS format into a
complete schematic circuit. Similar
facilities exist for the libraries as well
as the schematics.

2-D Lines and Add Text  Commands

The 2-D Lines and Text commands provide the
ability to create any general drawing item,
solid or dashed lines, filled or unfilled
polygons, title blocks, etc.,  and text
entries or notes in the schematic.  There
is also a 2-D Lines library capability, for
storing created items into the library for
use on other schematics or even within
PADS-PCB.

System  Reports

In addition to the netlist, job limits,
and Bill-of-Material reports that you have
already seen in the Reports menu, there are
a variety of analysis reports. These are:
o Net status, listing all the nets in the
schematic and any possible errors in the
nets.
o Part status, listing, for each part in
the circuit, its part type and the signals
connected to each pin.
o Unused, listing all unused gates and
unconnected pins in the parts in the
circuit.



PADS-Logic  allows you to define many user
libraries. You can locate these libraries
in any directory on your system, or even
keep the libraries on a central network
file server. To observe how the library
routine functions, go into the main menu
and select  SETUP (F8), LIB PATH (F4).    A
full menu will appear with the available
libraries.

The Library Merge Command

This command is used to copy library parts
from other schematics into your library. If
a colleague has created new library parts
which you also want to use, this command
saves you substantial time in copying these
parts into your library.

From the main menu, the Library Merge
command can be accessed by selecting Other
Menu (F9), Hier/Lib (F9), then Merge (F8).



Your Next Step


PADS-Logic is a powerful design tool, and
no short manual can adequately cover all of
the capabilities and features of the
product. If you have followed the exercises
and worked with the software on your own
circuits, you will have a good appreciation
of the advantages PADS-Logic has to offer
over other systems.

If your designs are small, this Shareware
version of PADS-Logic is more than adequate
to design your circuits, use it with our
compliments.

If you need the capability of designing
circuits with up to 1000 or more IC's, you
should consider the actual version of PADS-
Logic. Thousands of engineers are using
PADS-Logic today. It has all of the
features of this shareware version, plus
greatly expanded system limits, the ability
to design schematics with up to 256 sheets,
and it comes with a 320 page user manual
describing all of the commands of the
program in detail.   If you would like to
put the powers of PADS-Logic to work on
your next project, you can order  it from
your local authorized PADS Dealer or
contact PADS Software, Inc.
(telephone: [phone], fax: 508-486-
8217).

Once again, thank you for your time and
interest.  We welcome any additional
questions you may have about PADS-Logic or
any other of our PADS products.

When you have finished your evaluation of
PADS-Logic, feel free to make copies and
pass it on to a friend or colleague.

PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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PADS-Logic Evaluation Guide

                 PADS-Logic Evaluation Guide


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