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VUTRAX SOFTWARE ADVICE NOTICE
206 Issue 3- (4 July
2002)
USING VUTRAX FOR
STRIPBOARD (VEROBOARD)
Stripboard (also known
by its commercial name Veroboard in the UK) is pre-prepared wiring
board consisting of strips of copper, normally at
0.1" pitch, with holes drilled along each strip at
the
same pitch.
Components are conventionally mounted (or
Surface Mount components mounted on
conventionally soldered carriers), and the connections
accomplished by a combination of carefully
arranged alignments, wire links between strips, and cuts
in the strips made either with a knife or a
special tool. Using such boards, small circuits can be
prototyped or even produced in small
quantities.
Vutrax can be used
to automate and formalise design of such layouts, using
either the complete
schematic to layout approach, a simple pin-list, or even
a straight to layout approach.
- Prepare schematic, pin list or whatever,
or produce the basic layout directly (see taping
Table).
- Generate libraries at 0.1" pitch if
required.
- Make the Rats nest normally.
- Now make a .brd
file the right size and shape, and
include on it a recessive image of the
stripboard on layer 10. Copy and Paste this command file
into file veroboard.dex .
In this set of commands 80 = 8" wide, 50 =
5" deep:-
DEF W 60 L 10 SZ 2
GOTO 0 0
F H
*80;; RIGHT 100;; C H
GOTO 0 0
NOTE
*50;; DOWN 100;; COPY
Z F
Remove any spaces that your browser
happens to have added at the start of the lines
(particularly those starting '*')
Execute the created file through the menu, or by using
typed command X veroboard.dex
If the grid is ridiculously large for your project try
again with changed 80 and 50,
or use
Keep All Inside
from Edit > Boxed Items to
pick the area you want
- For cosmetic appearance, and to keep the
artwork within limited capacity system
allowances, you should now set up 2 pad shapes as
Annular rings.
Select Define Pad
from (Options > Pads & Tables), select pad 2 and change the pad from 'Assumed' to
'Annular Ring' with Inside = 16
and Outside =
32. Click
OK and
acknowledge the
dimensional warning you get.
Now move to pad 11 and do the same but with
Inside = 44 and Outside = 88.
You can change these dimensions later if you prefer
others.
- Merge the .brd into the rats nest in
the usual way. So you can see the rats nest, click on
the
layers/colour bar at the bottom of the window, and
change the colour of layer 0 (Magenta is a
good choice). While you are at it, on 16/24 bit colour
displays, select Mix display mode.
- Shuffle/turn the parts about until you
see a sensible layout. Remember to Optimise
interconnects, and/or repaint, if the layout gets in a
mess. Try to align a worthwhile number of
signals horizontally to save wire links. Particularly
worthwhile is to attempt to maximise
alignment of 0V (ground) and other Power supply
connections to discrete components.
Remember that conventional stripboard wire connections
requires an uncommitted
hole adjacent to the device pin, into which to
insert the wire. For easiest manufacturing
spread your design as much horizontally (along the line
of the strips) as you can.
- Route your efforts normally (using VIAs,
layer 1 for Horizontal, layer 2 for Vertical (these will
become wire links so minimise them.).
If you decide to use auto-routing use Basic Autorouting from (Tools >
Routing)
(AUTOTRAK) rather
than Ripup
Autorouting (VUROUTE), because its right
angled style
better fits the restrictions of Stripboard. Set the grid
to match the board pitch. You will
probably have to place a few tracks yourself when
AUTOTRAK has
finished - it does not rip
up and re-try. For suitable starting rules file Copy and
Paste this command file into file
veroboard.rul .
Don't worry about leading spaces here.
ONENODE N/C ;
TRACKS 1 2
WIRES 0 5
MINGAP 12
ENDRULES
PITCH 100
LEVEL 0
MAPGRID 8
VIASIZE 8
VERLAY 2 NODESFROM 5
HORLAY 1 NODESFROM 0
PASSES 0 10
SIGOPT EDIT
ENDAUTO
If your routing is not very successful,
update the placement in the light of congested areas
and unnecessary long connections, and try again.
- Manually modify the routing so that there
are no tracks existing vertically from component
pads - you will only be able to make such connections
by fudging joints of the copper side of
the stripboard. To find these try showing just layer 2.
Try to arrange that each track that has a
vertical run in it goes to a VIA on the same strip, and
then runs vertically to another VIA
on
another strip.
- You can check the routing by using
Save As to (say) temp.art,
and in this temporary copy
Delete all stripboard strips, and then use Design Check and Artwork Compare
from
(Tools > Routing)
- Mark cut points (places where a single
strip has to be cut to be used by more than one
signal) with Size 11 Node on
Layer 5 (magenta).
You previously defined Pad shape 11
as a
large Annular ring.
- According to how you work, print or
display flipped or normal images in colour or with layer
2
& 5 black and all else gray to show you where to
cut and link. The best selection of colour for
the strips depends on usage. We use dark blue on the
screen, and light blue for printing, with
tracks in Red, linked in Green
- All the top-down and backward
modifications work, except that you have to update the
cut
points yourself.
Vutrax is a big
system - you will need to work through the thorough
on-screen tutorials so you
know what is going on BEFORE you start varying the
scheme as above. If you want to use the
direct layout on to the grid, you should work through
the Taping Table
section of the tutorial when
you are prompted to after the basics sections - you
don't need to learn about schematics or library
building.
If you find a more convenient or
functional variations please let us know.
Distribution:
- Internet Site.
- Sent on Request.
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