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INTRODUCTION INTRODUCTION
Installation
First, place the distribution diskette into one of your floppy
drives. Log onto that drive and type
QINSTAL QINSTAL
followed by {Enter}.
You will be prompted for the destination drive and path to
receive the QiCAD files. When installation is completed, store
the distribution diskette in a safe place.
Before running QiCAD, you should edit the file DEVICE.SET to
contain the drive letter of your RAM drive. QiCAD requires a RAM
drive running above system memory for optimum operation. Many
third party RAM drives are available, and all DOS versions beyond
3.0 include a RAM drive, named RAMDRIVE.SYS. For information,
please consult your DOS manual or RAM drive user's manual.
If you encounter any problems installing QiCAD, please contact
Customer Support at
Voice: (702) 423-1653 0900-1700 PST
FAX: (702) 423-1654 24 hours
Typographical Conventions
Throughout this Manual, we use the following conventions for
representing user interaction:
Menu items are shown between square brackets, e.g.,
[PLACE]
Menu items in other than the current menu are shown with the menu
name, followed by a slash, followed by the menu item, e.g.,
EDIT/[ChgLyr]
Printing keys are shown in double quotes, e.g.,
"/" (the Pan function).
Non-printing keys are depicted with their key cap legends or
functional descriptions between angle brackets, e.g.,
{Enter} or {Backspace}.
In cases where key combinations are meant, they are shown
juxtaposed, e.g.,
{Ctrl}"x" (the Exit function)
Mouse buttons are defined as
{MouseR} = the rightmost mouse button
{MouseL} = the leftmost mouse button
{MouseLR} = {MouseL} and {MouseR} pressed together
Overview
The QiCAD PC Design System consists of the QiCAD Layout Editor, a
programmable batch autorouter, and an appropriate Library of
components. QiCAD's unique database combines physical size and
shape information with electrical wiring information to enhance
the PC design process. With QiCAD's approach, it is possible to
design a layout either from a netlist, or from "scratch," without
any reference to the electrical database. For some types of
designs, such as test fixtures, this is the preferred method. In
either case, the QiCAD Editor provides a rich set of tools for
creating printed circuit designs.
Designing with the electrical database involves adhering to a
predetermined sequence of steps.
First, you prepare a netlist of all the electrical connections in
the layout, and a parts list of all components used. You may
either type the netlist or extract it from one of the many
schematic drawing programs on the market. QiCAD can convert
netlists in popular "Schema" format; one product, SuperCAD, can
emit netlists in GAV format. Refer to the Tutorial section for
details on using netlists.
Second, you "read" the netlist into a blank layout to load the
parts and their connections. This process creates a "ratsnest
drawing," which is a collection of parts used in a layout,
connected by lines representing the electrical wiring.
Next, you use the positioning functions of QiCAD to move, rotate
and mirror the components into appropriate locations within the
board layout. The object of this step is to achieve a minimum of
wire cross-overs. An efficient placement results in much easier
routing later.
At this point, you may either begin routing the wires manually
using track bending and point-to-point autorouting, or submit the
ratsnest drawing to the batch autorouter. To run the Autorouter
you define a routing window, build the autorouter interface
files, and exit QiCAD.
Now, you are ready to autoroute. The AR Autorouter loads the
interface files and proceeds to insert routing tracks and vias
into the layout.
When the Autorouter has completed as many routes as possible, you
run re-enter QiCAD and load the autorouter data into routing
window.
Finally, you use QiCAD's editing functions to make last-minute
modifications.
If you wish to bypass the electrical database and design
manually, you need only enter QiCAD, draw the board outline, and
begin work. In manual layout, you select parts from the Library
using QiCAD's Menus, drag the parts into place, and connect them
using QiCAD's point-to-point autorouter. If you are designing
with repeated cells or arrays, you may choose to exploit QiCAD's
array features.
Once you have completed your layout, you may want to generate
data for photoplotting or drilling using QiCAD's CAM
capabilities, such as Gerber and Excellon output.
AUTOROUTING
The AR Autorouter included with QiCAD is quite powerful and
flexible. Nevertheless, AR will not do your thinking for you;
there is no substitute for careful design. What AR will do is ____
perform a large percentage of the wiring hookups for you. Chances
are, you would be able to produce a better looking layout
manually; autorouting is a trade-off between time and
aesthetics. In a typical autorouted design, AR will complete
about 80-90 percent of the connections in ten percent of the time
it would take you to do them. In order to exploit AR, you need
to understand the autorouting process and how AR approaches it.
Autorouters are programs which automatically convert from-to
wiring information into an orderly layout. Using a list of wires
and pad locations as input, autorouters follow various rules and
algorithms to create tracks and via pads. The routing process
poses a number of concerns: first, there must be a method for
representing the layout in memory; second, there must be some
means of detecting clearances between elements; third, there must
be a strategy for finding a free path; lastly, there must exist
criteria for selecting layers. Computer scientists have
developed numerous algorithms to address these concerns; GAV has
selected the venerable Lee Algorithm in implementing AR.
The algorithm, proposed by C.Y. Lee in 1961, envisions the
layout as represented by a rectangular array of points resembling
a sheet of graph paper. Each point of the layout can contain
only one of three things: empty space, a pad, or a track vertex.
The algorithm functions by searching in an ever-widening spiral
for free cells, leaving a marked trail back to the search origin.
The most common complaint about the Lee Algorithm is that it must
search n2 cells to find a route for a wire of length n; the search n2 cells to find a route for a wire of length n; the
algorithm is slow.
The AR ripup Autorouter uses a variant of the Lee Algorithm: the
search path can be constrained within user-defined bounds. AR
thus permits considerable control over the routing process by
allowing the user to alter the search characteristics as well as
other routing rules during a session. To accomplish this, AR
provides a batch programming script language.
AR reads control commands from a file named ROUTER.CTL. Commands
in this file set various rules, such as the number of vias, the
layers to be used, and so on. For detailed information on each of
the controls, consult the Reference section entitled, "Autorouter
Controls." The most important rules which AR uses in routing are
layer assignment and Sidetrack/Backtrack. BR assigns a wire to
either a layer containing mostly horizontal wires or mostly
vertical wires.
Sidetrack and Backtrack control how far AR searches to locate a
route for a given wire. When Side-and-Backtrack are both small,
routing will be confined within fairly tight channels, but rather
many wires may be rejected for routing. If Sidetrack and
Backtrack are loose, routes will tend to "meander," and the board
will tend to become clogged with tracks. A fuller discussion of
these important parameters is located in the Reference section.
QiCAD Database
QiCAD stores its working data in a file called QICAD.$$$. In
normal operation, this file resides on a RAM drive above system
memory. Consequently, data is preserved between sessions (unless
you reboot in the meantime). When you exit QiCAD or when you
select FILE/Save, QiCAD copies the file in the RAM drive to a job
file on the hard drive. When you select FILE/Load, the RAM drive
file is overwritten with the new job file.
Each entry in the database is either a Pad, a Track, a Window, a
Part Reference, a Label Tag, or a Signal. Pads and tracks
represent the physical information in the layout, while part
references and signals represent the electrical information. In
addition, pads and tracks may have electrical attributes. For
example, a pad can have a pin number attribute, a part reference
attribute, and a signal attributes. Tracks may have either part
reference attributes or signal attributes, but not both. Pads or
tracks with no attributes are considered to be neutral _______
electrically.
Each pad and track also carries physical information (size and
layer), and status information (selected, visible, or deleted).
An element's size actually describes the dimensions and shape of
an imaginary tool used to construct it. A track, for example,
might be defined with a round tool 0.010" x 0.010" in diameter.
The resulting track drawn with such a tool would be 0.010" wide
and would have rounded ends. A pad might be described with a
0.055" x 0.070" rectangular tool; the resulting pad would be a
0.055" x 0.070" rectangle.
This tool concept is based on the photoplotter data format, RS-
274. Following the photoplotting conventions, the tools are
called apertures, and the tool numbers used to refer to them are _________
called Dcodes. In photoplotter jargon, tracks are called draws ______ _____
and pads are called flashes.
The technique of using defined tools yields enormous advantages.
First of all (assuming you have the layout photoplotted), you
have a built-in photoplot viewer. Second, and more important, you
have a tokenized database. This means, for example, that you can
change all 0.015" tracks into 0.012" tracks simply by editing the
tool definitions. Finally, tokenization lets you exploit certain
advanced features of modern photoplotters, such as flood fills
and automatic groundplane generation.
Elements are located within a space of +/- 32000 units in X and
Y. Normally, units are construed to be mils (0.001"); all QiCAD ____
library parts are constructed in mil units.
QiCAD assumes the following layer conventions:
A is the pads layer
B is the component side
C is the solder side
B..G are autorouting layers
M is the routing window layer
N is the bottom silkscreen
O is the top silkscreen
P is the wire layer
REFERENCE
How to... How to...
...select an element
In order to add an element to the selection set you must use one
of the selectors, [Next], [All], [Wndo], or [EWndo]. _________
Use the [Next] selector by either picking it or typing the "+"
key. The next item in the database will be selected, and ____
everything in the prior selection set will be deselected. everything in the prior selection set will be deselected.
Use the [All] selector by either picking it or by typing the "*"
key. All items in the database at the current cursor location ___
will be added to the selection set. For the [Next] and [All]
selectors, the search diameter is one-tenth the current grid
setting.
Use the [Wndo] selector by picking it or by typing the {End} key.
All items with at least one vertex within the window will be
added to the selection set.
Use the [EWndo] selector by picking it or by typing the "e" key.
All items with at least one vertex within the window, and which
are of the current data mode type, and which are on the current
layer, will be added to the selection set.
...get help
Move the cursor to the menu item for which you want help and
click {MouseR}. Then, move the cursor out of the menu sidebar and
type the "?" key.
...zoom
Move the cursor to the position in the display which you want to
be the center of the new view and click {MouseL}. You may stop
the redraw by typing {Esc}.
...pan
Move the cursor to the position in the display which you want to
be the center of the new view and click {MouseR}. You may stop
the redraw by typing {Esc}.
...set the width display
Pick the [Width] selection or type the "w" key.
...set the grid interval
Select UTIL/[Grid] or type the "g" key. Supply the grid interval
in units and whether grid dots should be displayed.
...set gridsnap
Pick the [Snap] selection or type the "c" key.
...measure
Select UTIL/[Meas.] or type the "v" key. When prompted, move the
cursor to the beginning point of the distance to be measured and
click {MouseL}. Move the cursor to the other end of the distance
and read the dX,dY co-ordinates from the status line. Click
{MouseL} to save the measurement into the Skew Vector or {MouseR}
to discard it.
...load
Select FILE/[Load] and supply the job name without extents. The
contents of the present database are lost.
...save
Select FILE/[Save] and supply the job name without extents. The
contents of the present database are copied into the file
jobname.DB. The prior contents of jobname.DB are overwritten.
...quit
Select FILE/[Quit] or type the {Ctrl}"x" key. The contents of the
present database are preserved.
...change layers
Select the elements to be changed and pick [Layer] or type the
"L" key. Type the letter of the layer onto which the selection is
to be placed. Then, select EDIT/[ChgLyr] or type the "\" key.
This operation does not clear the selection set.
...change sizes
Select the elements to be changed and pick [Size]] or type the
"d" key. Type the number of the Dcode (tool) to which the
selection is to be set, followed by ""Q" to exit the Dcode
Editor. Then, select EDIT/[ChgSiz] or type the {Tab} key. This
operation does not clear the selection set.
...change data mode
Select LIBR/[ModeT] or type the "t" key to set the Track Data
Mode; select LIBR/[ModeP} or type the "p" key to set the Pad Data
Mode.
...add a pad
Set the size, layer, and gridsnap appropriately, and set the Pad
Data Mode. Select LIBR/[Add] or type the {Ins} key. Move the
cursor to the pad location and click {MouseL}. Continue until you
are finished adding pads and click {MouseR} to terminate the
command.
...add a track
Set the size, layer, and gridsnap appropriately, and set the
Track Data Mode. Select LIBR/[Add] or type the {Ins} key. Move
the cursor to the beginning point of the track and click
{MouseL}. Move to the end point of the track and click {MouseL}.
Continue until you are finished adding Tracks and click {MouseR}
to terminate the command.
...add a part
Select LIBR/[Insert] or type the "i" key. Supply the part name
with extent, move the cursor to the desired insertion point, and
click {MouseL}. If the part requires a reference designator,
supply it when prompted. The contents of the part are added to
the selection set.
...create heat reliefs
There are two methods. The preferred is to place tie bars on a
special connection layer for each plane. The final plane artwork
is created at the photoplotter by
(1) plotting the pad set oversize and negative, and then
(2) plotting the pad set right size, positive, and finally,
(3) plotting the appropriate tie bars right size positive.
This entire operation can be done without removing the film from
the plotter.
The second method is to create a non-electrical thermal pad(on
the plane layer) using tracks and superimpose it on the
appropriate part pin.
...add text
Set the size, layer, and gridsnap appropriately, and select
UTIL/[Text] or type the "$" key. Supply the text string to be
inserted and move the cursor to the insertion point. Click
{MouseL} to insert the text, which is added to the selection set.
...list selected elements
Select UTIL/[List]. When the listing is complete, type any key to
return to the display.
...list the database
Select FILE/[DBList]. When the listing is complete, type any key
to return to the display.
...move elements
Select the elements to be moved and then pick EDIT/[Move] or type
the {Space} bar. Click {MouseL} at the datum point of the move
and again at the new location. The selection set is not cleared.
...delete elements
Make sure that only those items which are to be deleted are in
the selection set. Select EDIT/[Del] or type the {Del} key.
Deleted items may be recovered with UTIL/[Undel] until the
database is purged.
...rotate elements
Select the elements to be rotated and move the origin to the
desired center of rotation by picking [Orig.] or typing the "o"
key. Then, pick EDIT/[Rot90] ("{") or EDIT/[Rot...].
...mirror elements
Select the elements to be mirrored and move the origin to the
desired reflection point by picking [Orig.] or typing the "o"
key. Then, select EDIT/[Mirror].
...change an element's shape
Select [Size] or type the "d" key. Enter the Dcode (tool) number
of the element in question. Use the X, Y, and Shape fields of the
Dcode Editor to re-define the tool. Type "Q" to exit the Dcode
Editor, and the display will be redrawn to reflect the change.
Note that all elements using this tool will be changed; to change
just one element, use EDIT/[ChgSiz] to change it to another tool.
...set the part reference
Select PLACE/[SelPrt] or the "q" key and enter the part reference
to set. Note that this function is case-sensitive. The contents
of the part is added to the selection set; type "u" to clear the
selection set, if desired. Setting the part reference to "NULL"
makes the current part reference neutral.
...set the current signal
Select ROUTE/[SelSgl] or the "j" key and enter the signal name to
set. Note that this function is not case sensitive. All elements
of this signal are added to the selection set; type "u" to clear
the selection set, if desired. Setting the signal reference to
"NULL" makes the current signal reference neutral.
...add label tags
Select LIBR/[Tag] or type the key "_" ({Underscore}). From the
Tag Submenu, type "L" and click {MouseL} to indicate the desired
label location. Supply the height of the label text, label
rotation, and the desired label layer. QiCAD inserts the word
"LABEL" at the selected location. The label tag will remain until
it is processed during LIBR/[Create] or until the database is
purged. Type "Q" to quit the Tag Submenu.
...add pin number tags
Select LIBR/[Tag] or type the key "_" ({Underscore}). From the
Tag Submenu, type "P", click {MouseL} to select a pad to tag, and
supply the pin number. QiCAD draws the pin number. Type "Q" to
quit the Tag Submenu.
...set or change an element's part reference
Use one of the selectors to choose the element to be tagged.
Pick LIBR/[Tag] or type the key "_" ({Underscore}). From the Tag
Submenu, type "R" and supply the reference designator with which
the element is to be tagged. Type "Q" to exit the Tag Submenu.
...set or change an element's signal reference
Use one of the selectors to choose the element to be tagged.
Pick LIBR/[Tag] or type the key "_" ({Underscore}). From the Tag
Submenu, type "S" and supply the signal reference with which the
element is to be tagged. Type "Q" to exit the Tag Submenu.
...create a part
Use one of the selectors to choose the elements to be included in
the part. If the part is to be referenced, be sure that a label
tag is included in the selection. Make sure that all pads are
tagged with appropriate pin numbers, if necessary. Pick
LIBR/[Create] or type the "a" key and supply the part name
(including extent) in which the elements are to be stored. The
part is stored in the library subdirectory, and any previous part
bearing the same name is overwritten.
If the part is to be called from a netlist, the extent must be
.PRT.
...create surface mount parts
Draw the part to be created with the component outline on the
appropriate layer and place the lands on the corresponding etch
layer. Note that layer B is considered to be the component etch
layer and C the solder etch layer.
The main issue with SMD parts is how the lands are constructed.
If you use pads with PLCC-type devices, you must use a separate
Dcode for each orientation, if you use tracks, you will get
obround lands, rather than rectangular ones, and you will have
to include a pad at the end of each land to indicate a connection
point and hold pin numbers.
If you intend to use the autorouter with SMD's you will also have
to include via connections with the part.
Once you have drawn all the elements in the part, use
LIBR/[Create] in the normal manner.
...make an electrical part
Electrical parts must have label tags and pin numbers. Use
LIBR/[Tag] to add these and then use LIBR/[Create] in the normal
manner to create the part.
...read a netlist
First, zoom out so that the entire board outline, and a few
inches beyond it, is visible. Pick PLACE/[RdNets] and supply the
netlist name, including extent. As the parts are called from the
netlist, click {MouseL} to position them loosely around the
outside of the board outline, being careful not to overlap them.
When all the parts have been called, QiCAD will draw the
ratsnest.
...change a part reference
Select PLACE/[UpdPrt] or type the {Alt} "N" key. Enter the
reference designator to set and then type {Enter} when prompted
for the new reference.
...change a part name
Select PLACE/[UpdPrt] or type the {Alt}"N" key and supply the
name to changed, followed by the new name. You will be reminded
to update any label text.
...change a signal name
Select ROUTE/[UpdSgl] or type the {Ctrl}"V" key and supply the
name of the signal to change, followed by the new signal name.
...move a part and its wires
If the part is an electrical part, use PLACE/[SelPrt] to select
it, otherwise, use the [Wndo] selector to enclose the part. Pick
PLACE/[Move] or type the {Space} bar to move the selected
elements.
...bend a wire
Use ROUTE/[SelSgl] to set the signal, followed by "U" to clear
the selection set. Then, use one of the selectors to pick the
wire to bend. Select ROUTE/[Bend] and click {MouseL} to set the
location of the added vertex.
...unbend a wire
Use ROUTE/[SelSgl] to set the signal, followed by "U" to clear
the selection set. Use one of the selectors to choose two
adjoining tracks and then ROUTE/[UnBend]. the coincident vertex
will be removed and a single track created.
...Autoroute point-to-point
Zoom up so that grid dots are visible, making sure that the width
display and gridsnap are on. Pick ROUTE/[Aroute] and click
{MouseL} to set the first point of the track to be routed. Click
{MouseL} again to set the other end of the track. If a route
exists within the displayed window, QiCAD will create it.
...add a via
Select ROUTE/[Via] and click {MouseL} at the desired via
location. QiCAD will insert a D27 pad at this location. To change
the default via tool, edit the file VIA.SET.
...make a routing window
Select ROUTE/[RWndow] and enclose the area to be windowed. Be
sure that the grid is set to some multiple of the desired routing
grid and that gridsnap is on.
...create autorouter data
select the window to be used by moving the cursor inside it and
typing the "*" key (the All selector). Pick ROUTE/[Make] and
supply the job name for the window data.
...load autorouted data
select the window to be used by moving the cursor inside it and
typing the "*" key (the All selector). Pick ROUTE/[Pour] and
supply the job name for the data to be loaded into the window.
...program the autorouter
Edit the file ROUTER.CTL to contain the desired program. Consult
the section entitled "Batch Script Command Language" for details.
...adjust the routing grid
Edit the file ROUTER.INI to adjust the grid setting. Consult the
heading "Global Settings" under the "Autorouter Rules" section
for details.
...adjust the router settings
Edit the file ROUTER.INI to adjust the setting. Consult the
heading "Global Settings" under the "Autorouter Rules" section
for details.
...create curves
Select UTIL/[Curve] and click {MouseL} once at each control point
for the curve. QiCAD will construct a Bezier spline within the
control points, made of electrically neutral joined tracks on the
current layer.
...create corners
Use UTIL/[Curve] such that the third and fourth control point
coincide. If distances 1-2 and 2-3 are equal, the result will
approximate a 90 degree arc section. You must tag the tracks
making up the corner with the appropriate signal or part
information.
...create doglegs
Use UTIL/[Curve] such that the control points describe a stair
step, where distances 1-2, 2-3, and 3-4 are equal. The result
will be a smooth dogleg between point 1 and 4. You must tag the
tracks making up the corner with the appropriate signal or part
information.
...create circles
Pick UTIL/[Circle] and click {MouseL} at the desired center
point. Supply the radius is units and QiCAD draws a circle made
up of tangent tracks. You must tag the tracks making up the
corner with the appropriate signal or part information.
...create solid areas
Use LIBR/[Add], UTIL/[Curve], or UTIL/[Circle] to create an
enclosed polygon. Tag the polygon with the appropriate electrical
information and then select it with one of the selectors. Pick
UTIL/[Hatch] and supply the fill pitch in units. QiCAD adds fill
tracks of the same layer and electrical value as the polygon.
Alternatively, if you will be photoplotting on equipment which
supports flood fills, you may construct the bounding polygon with
a Dcode of D100. QiCAD will depict the inside of this area as
solid, but will not perform gap checking within it. You must tell
your photoplotting vendor that D100 is a flood fill boundary.
...create arrays
Choose the elements to be arrayed with one of the selectors. Pick
UTIL/[Array] and provide the information prompted for. QiCAD
clears the selection set and then constructs the array, adding
the new elements to the selection set.
...perform gap checks
Select UTIL/[Check] and supply the clearance to be checked for.
QiCAD will insert a cross on layer M at each violation.
...change all of one size to another
Set the size code to change TO, and then pick UTIL/[Xcode] or
type {Shift}{Tab}. Supply the tool number of the size to changed
FROM. Every element with the FROM size will be changed to the TO
size.
...scale elements
Choose the elements to be scaled with one of the selectors and
pick UTIL/[Scale]. Supply the new X and Y scale to apply to the
selection set. QiCAD will change the co-ordinates of all elements
in the selection set relative to the origin. Note that due to
round-off errors, this operation is not always exactly
reversible.
...create Gerber files
Select a layer which is not to be output and pick OUTPUT/[Freeze] ___
to disable it. Repeat this process for all unwanted layers. Then,
pick OUTPUT/[Gerber] and supply the file name to receive the
data. You are given the option of writing an aperture list.
...create checkplots
Select a layer which is not to be output and pick OUTPUT/[Freeze] ___
to disable it. Repeat this process for all unwanted layers. Then,
pick OUTPUT/[CkPlot] and from the Plot Submenu, set the pen
width, scale factor, and language. Type "B" to begin plotting.
The plot data is sent to the file QICAD.PLT.
...create PostScript files
Select a layer which is not to be output and pick OUTPUT/[Freeze] ___
to disable it. Repeat this process for all unwanted layers. Then,
pick OUTPUT/[PostSc] and supply the job name to receive the data.
You are given the option of creating groundplane. Data is sent to
the file jobname.PSC.
...create drilling programs
Pick OUTPUT/[Drill] and supply the job name to receive the data.
QiCAD creates the file jobname.DRL. _______
...export layouts to AutoCAD
Pick OUTPUT/[Acad] and supply the job name to receive the data.
QiCAD creates the file jobname.SCR. This file can be loaded into _______
an AutoCAD drawing by issuing the SCRIPT command.
