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SERIAL LCD DRIVER
for PCs, PICs, PICAXEs, Stamps . . .
We detest the oft-used buzz words “human interface” but that is just
what this project is: an interface between a 2400 baud serial line
(inverted or non-inverted) from a PC, PICAXE or other processor and
common character-type LCD displays which use the HD44780 interface.
Design by Graeme Matthewson . . . Article by Ross Tester
W
hile there is nothing particularly new or innovative
about this design, it has two
huge advantages over anything similar
that is currently available: (a) it is very
simple; and (b) it is very cheap.
In fact, it is much cheaper than anything that does the same or similar job
and provides a very low cost way to
turn serial data into words.
You can use a variety of LCD displays, with provision on the PC board
for the most common types.
Features include variable backlight
intensity (software controlled), two
auxiliary digital outputs and a “beep”
output to drive a piezo speaker.
The photo above shows the interface
74 Silicon Chip
(highlighted, centre) driving a typical
LCD display (in this case a DL-6 from
Oatley Electronics) from a lashed-together battery voltage monitor driven
by a PICAXE 08M.
It’s nothing special but gives just
one of many practical uses for this
project.
TTL interface
The serial interface is at TTL levels
– that is, the idle state, is at TTL logic
one, or near +5VDC.
Therefore you can interface directly
with any project offering TTL level
outputs.
You can also interface with PICAXE
projects, using the “SEROUT” com-
mand with the T2400 (ie, 2400 baud)
specifier.
Backlight control
The backlight current is controlled
by an on-board transistor. You have
the choice of two resistors to set the
maximum current – 4.7W for 5V operation or 39W for 12V.
Display contrast is set by two fixed
value resistors, 4.7kW and 330W,
which provide a nominal 0.3V DC for
contrast. However, you may wish to
change these values to achieve different contrast levels.
The serial LCD interface has a 64-byte
receive buffer and the ability to interface with a variety of LCD geometries,
siliconchip.com.au
EEPROM storage of the LCD geometry
setup, eight user-defined characters,
tab size and cursor style plus a rich
plain language instruction set.
A supply of 5V DC with a minimum
10mA is required for this circuit. If the
backlight is used, the supply current
needs to be increased accordingly.
The Oatley Electronics kit includes
a PC board, a programmed PIC16F628
or similar PIC IC, onboard components
and input/output connectors. Note
that the kit does not include an LCD
because of the wide variety available
and the individual uses to which this
project will be put.
Oatley themselves have a variety
of LCDs available – more information
is available from their website (www.
oatleye.com).
Finally, a warning: the PIC processor
is code-protected and the source code
is not provided. Any attempt to read
the chip’s code will erase the program
in the chip and render it unusable!
Assembly
The project is very simple to construct with just one IC, a crystal, two
transistors and a sprinkling of other
small components.
+5V
REGULATED
We’ve published this picture
significantly larger-than-life to show
how the board can be snapped off
between the two sockets, if required.
Start with those small components
– resistors, a capacitor, diode and the
transistors. The only components
where you need to worry about polarity are the diode and transistors.
+5V
100nF
14
Vdd
4.7k
4
RESET
2
MCLR
RB6
12
4
4.7k
Vdd
RS
LCD MODULE
8
TEST
10
AUX OUT 4
11
AUX OUT 5
SPEAKER
330Ω
6
RB7
RA3
RB4
IC1
SERIAL
DATA IN
4.7k
B
K
D1
1N4148
RA1
RA0
RB0
RB3
R/W
5
2
R1
4.7Ω
1
BACKLIGHT
SUPPLY
18
Q2
C8050
17
330Ω
9
B
C
OSC2
Rx
E
OSC1
Vss
5
15
16
RES1
4MHz
R1 = 4.7 Ω FOR 5V.
39 Ω FOR 12V
C8050
1N4148
2005
330Ω
KBL ABL
16
15
A
SC
3
E
7
C
RA2
RB5 LCD108
CONTRAST
EN
D7 D6 D5 D4 D3 D2 D1 D0 GND
1
14 13 12 11 10 9 8 7
4.7k
Q1
C8050
6
13
RB2
+5V
INVERTED
SERIAL
DATA IN
Note that all resistors and the diode are mounted vertically on the PC
board, as shown in both the diagram
and photos. Mount the components
right down on the PC board to mini-
SERIAL LCD DRIVER
A
B
K
C
E
The IC does all the translation from serial data to display it on a variety of LCD readouts. Both inverted and noninverted data can be inputted, making it a very versatile device indeed!
siliconchip.com.au
August 2005 75
.
1
4.7k
4.7k
330Ω
4.7k
4.7Ω
RES1
D1 4.7k
100nF
IC1 LCD108
Q2
C8050
330Ω
1
.
330Ω
SNAP OFF HERE IF NOT USED
2
1
16
15
16
Q1
C8050
.
.
mise the chances of shorting to the
back of the LCD board (assuming that’s
where it will be mounted). In fact, it
would be a good idea to place a sheet
of insulating material between the serial interface PC board and your LCD
to avoid mishaps.
There are two wire links on the PC
board, both clearly marked on the
screen-printed overlay. You should be
able to make both of these from cut-off
resistor leads
Now you can solder in the IC socket
– its notch is oriented the same way
as the symbol on the PC board – but
don’t insert the IC yet. Leave that
until last.
Solder in the input socket – be very
careful as the spacing doesn’t leave
much scope for poor soldering.
The input socket is a right-angle
mounting type, meaning the input
lead will depart from the board in the
same plane.
Similarly, solder in the LCD connector sockets – both are included
in the kit (to suit 14 or 16-pin LCDs)
and even if you never use one, having
BACKLIGHT
SUPPLY IN
REGULATED +5V IN
RESET
SPEAKER
INV SERIAL DATA IN
GROUND
SERIAL DATA IN
AUX OUTPUT 4
AUX OUTPUT 5
TEST
Here’s the component
overlay with a samesize photo alongside
for comparison.
As you can see,
provision is made to
snap the board off
at the long socket if
you don’t plan on
using the double-row
socket.
both on the board makes the project
that much more versatile for those
who might want to swap LCD types
at a later stage.
However, if you will definitely only
use the 16-pin (in-line) socket and
would like to make the board a tad
smaller, you can ignore the 14-pin
(dual row) socket and snap the board
off where marked, adjacent to the inline socket.
Note that no provision for mounting
holes is made on the PC board – it is
envisaged that the board would be
more-or-less used “in line”, or mounted on the back of the 40 x 2 display,
as shown overleaf.
If you need mounting holes and do
not need the 14-pin socket, we suggest
you drill a couple of holes in the corner
of the PC board above and below where
that socket would go, taking care to
remove any copper around the edges
of the holes.
This is easily done by hand-twisting
a (say) 5mm drill bit in the hole on the
copper side of the board. Its edges act
like a blade, removing any copper from
around the hole sides.
PC board connections
“B”
Backlight power supply connection. Can be linked to the +5V
connection or powered from an
external supply (eg, 9V or 12V
DC etc). The kit is supplied with
a 4.7W resistor for 5V use. For
12Vdc use a 39W.
“+5” The 5V DC input. This needs
to be a clean regulated supply
at around 10mA; more if you
power the backlight from the 5V
DC (the current required will
depend on your backlight).
“R”
The RESET connection. It has
a 4.7kW pullup resistor to 5V.
When the input is pulled to
GND momentarily it will reset
the chip and display.
Parts List – Serial LCD Driver
1 PC board, code K221, 45 x
40mm
1 10-way IDC connector,
right-angle PC-mount
1 16-way (or 4 x 4-way) PC-mount
header socket strip
1 16-way (2 x 8-way) PC-mount
female socket strip
1 18-pin DIL IC socket
1 LCD module to suit (see text)
Semiconductors
1 pre-programmed PIC microcontroller (labelled LCD108) (IC1)
2 C8050 general purpose NPN
transistors (Q1,Q2)
1 1N4148 diode (D1)
1 4MHz ceramic resonator
Here are just two of the range of liquid crystal displays (LCDs) which can be used
with this driver. Both are from Oatley Electronics – at top is the 16 x 2 DL6 which
sells for $12.00, while the lower one is a DL13, a 40 x 2 display which sells for
$25.00.
76 Silicon Chip
Capacitors
1 100nF MKT polyester
Resistors (0.25W 1%)
4 4.7kW 3 330W 1 4.7W
siliconchip.com.au
Connecting an Oatley DL6 display
1
Some LCDs use pins 15 and 16 to connect to their backlights. The PC board provides these connections.
Other LCDs use two connections at one end of the display
and will need to be connected to the PC board with some
additional wire. The wiring shown in (a) is the minimum
required to operate the Oatley Electronics DL6 display. The
backlight of the DL6 is directly connected to +5V and GND
and is on permanently.
The DL6 also has some additional features; eg, a pushbutton microswitch, a bicolour LED and a piezo speaker.
The extra connections shown in (b) as dark wires allow the
use of the additional features of the DL6 display. With this
configuration, the display will momentarily go into test mode
when the switch is pressed. If digital output #4 is addressed,
the LED will glow red. If digital output #5 is addressed, the
LED will glow green. The piezo speaker will also beep when
addressed. For details on addressing inputs and outputs,
see the programming section of these notes.
“SP” The speaker output. The chip
outputs a short burst (“BEEP”)
which can be connected to a
peizo speaker
“D”
An input designed to take inverted serial data from an RS232
port (eg, a PC etc).
“–”
The GND or 0V connection.
“D”
An input designed to take noninverted, logic-level serial data
from a micro such as a PICAXE,
PIC or BASIC STAMP etc.
“#4” and “#5” Digital outputs which
can be used to switch other
devices or an indicator LED, etc.
“T”
The TEST input. Holding this
to GND while rebooting the
processor will show the test
siliconchip.com.au
(a)
1
1
(b)
display on your LCD. No pullup
resistor is required.
Configuration commands.
Warning: Do not include configuration commands in software loops.
Although the EEPROM can be written many hundreds of thousands of
times, in a software loop the life of
the EEPROM could be used up very
quickly. It is best to not use configuration commands in your final software.
Note: Commands are case sensitive.
A number of parameters are stored
in the processor, including the geometry of the LCD, the type of cursor, the
number of spaces in a tab and the eight
user-defined characters.
The settings of all of these are displayed briefly on the LCD when the
processor boots.
The default is a 20 x 4 LCD, a tab
size of 4, a full blinking cursor (3) and
1
the eight special user-defined characters. All of these parameters may be
modified.
Note that when the modifications are
made, the new values are written to the
processor’s EEPROM. Thus, the userdefined characters and the geometry of
the LCD need only be modified once.
Set LCD geometry
Setting the geometry (size) defines
the configuration of the interfacing
LCD.
?Gyxx “?G216” will set the LCD to
2X16 configuration. Valid entries –
some include ?G216 (2X16),?G220
(2X20),?G224 (2X24),?G240 (2X40),
?G416 (4X16) and ?G420 (4X20).
The configuration is important for
the processor to properly position
the cursor after each text character is
(Continued on P80)
August 2005 77
78 Silicon Chip
siliconchip.com.au
‘ Be sure Tx Pin is idle for some time
‘ wait for PICAXE LCD to boot
‘ configure LCD as 4 X 20
‘ clear the LCD and home the cursor
SerOut 0, T2400, (“?G420”)
SerOut 0, T2400, (“?f”)
‘ Variables used in PWMDemo
‘These variables are used in Sub SerOutByteHex
‘These variables are used in Sub BarDemo
High 0
Pause 5000
Symbol Duty = B9
Symbol NN = B8
Symbol LeftOver = B9
Symbol Num_5 = B10
Symbol J = B11
Symbol X = B8
Symbol N = B2
Symbol OWord = W0
Symbol OByte = B3
‘
‘ Configures the interfacing LCD for 4X20 geometry.
‘ This need only be done one time as this is saved in the K221 EEPROM
‘
‘ Clears the LCD using the “?f” command.
‘ Writes some text. Note the new line function “?n”
‘ Displays the user defined characters using commands ?0, ?1, etc
‘ Moves cursor to line 1, col 00 using commands “?y1” and “?x00”
‘ Clears lines 1, 2 and 3 using “?l” command.
‘ Note “?j” is used for down cursor.
‘
‘ Positions cursor at line 1 and displays the values of N and Word in
‘ decimal and in Hexadecimal.
‘
‘ Defines new user defined characters consisting of no vertical lines,
‘ 1 vertical line, etc through 5 vertical lines.
‘
‘ A bar scaled to 0 through 25 is displayed on line 3.
‘ This might be used to graphically display a quantity.
‘
‘ The PWM duty cycle is then set to 25 steps over the range of
‘ 00 to 250 using the ?B command.
‘ The duty cycle is also displayed on the LCD.
‘
‘ The program then continually sets the two general purpose outs to
‘ 10 and 01 using the ?H and ?L commands.
‘
‘ Written by.... Peter H Anderson, Baltimore, MD, Feb, ‘04
LeftOver = LeftOver + 48
SerOut 0, T2400, (“?”, LeftOver)
For N = 0 to 25
SerOut 0, T2400, (“?y3?x00?l”)
NN = 4 * N
NN = 100 - NN
Num_5 = NN / 5
LeftOver = NN % 5
For J = 1 to Num_5
SerOut 0, T2400, (“?5”)
Next
For N = 0 to 25
SerOut 0, T2400, (“?y3?x00”)
NN = 4 * N
Num_5 = NN / 5
LeftOver = NN % 5
For J = 1 to Num_5
SerOut 0, T2400, (“?5”)
Next
LeftOver = LeftOver + 48
SerOut 0, T2400, (“?”, LeftOver)
Next
BarDemo:
AGAIN:
SerOut 0, T2400, (“?H5?L4”)
SerOut 0, T2400, (“.”)
Pause 500
SerOut 0, T2400, (“?L5?H4”)
SerOut 0, T2400, (“!”)
Pause 500
GoTo AGAIN
Pause 200
GoSub PWMDemo
Pause 200
‘ convert to a character
‘ decreasing bar
‘ convert to a character
‘ increasing bar
‘ continually bring outputs 5 & 4 hi and lo
‘ cursor to beginning of line 3 and clear line
SerOut 0, T2400, (“?y3?x00?l”)
GoSub BarDemo
‘no cursor
SerOut 0, T2400, (“?c0”)
Pause 200
SER_LCD.Bas – Illustrates many capabilities of the Serial LCD Interface (written for the PICAXE 18X)
siliconchip.com.au
August 2005 79
PICAXE LCD?n”)
‘ position cursor at beginning of row 1
‘ clear lines 1, 2 and 3 and start at line 1
‘ note the use of down cursor command
SerOut 0, T2400, (“?y1?x00”)
SerOut 0, T2400, (“?l?j?l?j?l?y1”)
OWord = 12345
‘ display a word in decimal
‘ and in hex
SerOut 0, T2400, (#OWord, “?t”)
GoSub SerOutWordHex
SerOut 0, T2400, (“?n”)
‘ define special characters
‘ delay to allow EEPROM to program
SerOut 0, T2400, (“?D00000000000000000”)
Pause 200
SerOut 0, T2400, (“?D51f1f1f1f1f1f1f1f”)
SerOut 0, T2400, (“?D41e1e1e1e1e1e1e1e”)
Pause 200
SerOut 0, T2400, (“?D31c1c1c1c1c1c1c1c”)
Pause 200
SerOut 0, T2400, (“?D21818181818181818”)
Pause 200
SerOut 0, T2400, (“?D11010101010101010”)
Pause 200
‘ beep
SerOut 0, T2400, (“?g”)
Pause 1000
Next
OWord = OWord + 1
‘ display in hex
‘ display in decimal
OByte = N
GoSub SerOutByteHex
SerOut 0, T2400, (“?t”)
SerOut 0, T2400, (#N)
SerOut 0, T2400, (“?t”)
‘ locate cursor to beginning of line 1
‘ pause to admire
Pause 2000
For N = 0 to 25
SerOut 0, T2400, (“?x00?y1”)
‘ display special characters
‘ note new line
SerOut 0, T2400, (“?0?1?2?3?4?5?6?7?n”)
SerOut 0, T2400, (“www.phanderson.com?n”)
Pause 100
SerOut 0, T2400, ( “
Return
OByte = OWord / 256
GoSub SerOutByteHex
OByte = OWord % 256
GoSub SerOutByteHex
SerOutWordHex:
Return
SerOutByteHex_2:
SerOut 0, T2400, (X)
If X <= 57 Then SerOutByteHex_2
X=X+7
X = Obyte % 16
X = X + 48
SerOutByteHex_1:
SerOut 0, T2400, (X)
If X <= 57 Then SerOutByteHex_1
X=X+7
SerOutByteHex:
X = OByte / 16
X = X + 48
Return
SerOut 0, T2400, (“?f”)
SerOut 0, T2400, (“?B00”)
SerOut 0, T2400, (“?B”)
GoSub SeroutByteHex
Pause 200
Next
‘ it is alphabetic; A, B, C, D, E, F
‘ low nibble
‘ add the character ‘0’
‘ it is alphabetic; A, B, C, D, E, F
‘ high nibble
‘ add the character ‘0’
‘ clear the LCD
‘ set PWM to 0
‘ backlight control
PWMDemo:
SerOut 0, T2400, (“?f”)
‘ clear the LCD
SerOut 0, T2400, (“ PWM Duty Demo?n”)
For N = 0 to 25
Duty = 10 * N
SerOut 0, T2400, (“?l”)
OByte = Duty
GoSub SerOutByteHex
‘ display the PWM in hex
Return
Next
Connecting an Oatley DL13 display
11
The biggest advantage of this display (apart from the extra characters,
of course) is that it can plug directly onto the driver board via the outer
(double row) socket.
Therefore it doesn’t need any cabling
– all you have to do is make sure you
get it the right way around. The photo
at right shows the correct position.
Some LCDs have a dual row of seven
or eight pins at one end while others
have a single row of 14 or 16 pins
along one edge.
The driver described here will plug
Single row type connection
directly on to either
type of display, as
shown below.
11
1
Single row type connection
Dual row type connection
displayed and in executing such commands as backspace, up cursor, down
cursor, new line, etc.
Cursor style settings
The style of the cursor may be set
using the ?c command.
“?c3” where the number is in the
range of 0-3.
Valid entries; 0, 2, 3.
0 configures as no cursor.
2 configures the cursor as nonblinking.
3 configures the cursor as blinking.
As with the set geometry and set
tab, the style of the cursor is saved to
the EEPROM.
Setting tabs
The tab size may be adjusted;
“?sx” – Valid entries; 1 - 8. “?s5” will
set the tab size to 5 characters wide.
When this command is received
by the processor, the new tab size is
written to EEPROM and this value is
used thereafter when executing the ?t
command.
With the ?t command, the cursor is
advanced, and characters in its path
are overwritten with a space.
?h – Backspace
?i – Forward cursor
?j – Up cursor
?k – Down cursor
?l – Clear current line and leave cursor
at the beginning of the line
Backlight intensity
?m – Position the cursor at the beginThe intensity of a LED backlight on Dualning
current line.
row of
typethe
connection
the associated LCD may be adjusted;
?n – Advance to the beginning of the
“?B80” Valid entries; 00 - ff
next line and clear current line.
Note that the digits following the ?t – Advance the cursor one tab.
“B” are 2-digit hexadecimal (00= off, ?? – Display the character ‘?’.
ff= full on).
The cursor may be set to any poThe output is used to switch the sition using the x and y commands
duty cycle of a transistor which con- below;
trols the average backlight current.
?y0
?x15
LCD commands.
Note that the line number follows
A partial list of various commands the ‘y’ command and the column numfollows. Note that all commands are ber, consisting of two digits, follows
prefaced with a “?” and the commands the ‘x’ command.
are case sensitive.
Thus, outputting the string
?a – Set cursor to home position.
“?y1?x10Hello?n” positions the cursor
?b – Destructive backspace (removes at column 10 of line 1 and then prints
character)
“Hello”, followed by a new line which
?f – Clear LCD and leave cursor in the also clears the next line.
home position
Note that the line and column
?g – Beep, outputs a 50ms burst of numbers begins with 0. Thus, for a 4
around 500Hz on the “B” connection x 20 LCD, valid lines are 0 - 3 & valid
on the driver board.
columns are 00 - 19.
For example, if the cursor is in column 3 and the tab size is 5, the cursor
will advance to column 5.
Anything in columns 3 and 4 will
be replaced with spaces.
1
Resistor Colour Codes
1
1
1
No.
1
1
1
Value
4.7kW
330W
4.7W
80 Silicon Chip
4-Band Code (1%)
yellow violet red brown
orange orange brown brown
yellow violet gold brown
5-Band Code (1%)
yellow violet black brown brown
orange orange black black brown
yellow violet black silver brown
User-defined characters
User-defined characters may be entered using the ?D command:
“?D300000000001f1f1f”
The first number after the ‘D’ is the
location where your user-defined character is stored in the EEPROM, In this
siliconchip.com.au
case user-defined character 3.
This is then followed by the eight
data bytes expressed in two-digit hexadecimal. Note that the hexadecimal
letters must be lower case.
In this example, lines 0, 1, 2, 3 and
4 consist of no pixels and lines 5, 6
and 7 consist of all five pixels.
Thus, when user-defined character 3
is displayed using the command ?3, a
character consisting of the lower three
lines will be displayed.
D3
00
00
00
00
1f
1f
1f
location
OOOOO
OOOOO
OOOOO
OOOOO
######
######
######
Any of eight user defined characters may be displayed using the
digits 0 - 7.
Thus, “?5?2” causes user-defined
character 5 followed by user character
2 to be displayed on the LCD.
Each user-defined character is saved
in EEPROM.
This kit provides a 64-byte serial
receive buffer. However, be careful. If
you are defining all eight user defined
characters, this involves sending 19 *
8 or 152 characters.
Writing each of the eight bytes to
EEPROM requires 15ms or more and
thus, one can easily over run the buffer.
Rather, provide a 1-second delay after
defining each character.
Direct control of the LCD.
Commands may be directly passed
to the LCD using the ?! command;
“?!01” sends the 01command directly to the LCD which clears the
LCD.
Caution
With all other commands the pro-
gram keeps track of the current cursor
position. This is not done with commands sent directly to the LCD using
the ?! command.
Thus, if the user configures the
LCD such that the cursor is located at
some point, subsequent line feeds and
similar will not work correctly as the
program does not know the current
cursor location.
Clearly, if the ?! command is used
to place the LCD in a mode such
that the cursor is decremented with
each character or the display itself is
scrolled, the subsequent operation of
the LCD which assumes an incrementing cursor and a fixed display will give
unpredictable results.
GP auxillary outputs
The K221 kit provides two general
purpose TTL outputs. Either of these
outputs, 4 and 5, may be brought
high or low using the ‘H’ and ‘L’
commands.
“?H4?L5” brings output 4 high and
output 5 low. Valid entries, 4 or 5.
On power up, all outputs are at a
high impedance (configured as inputs). As each output is addressed,
it is taken out of the high impedance
state.
The initial high impedance state
permits the user to use either pull-up or
pull-down resistors to avoid “bounce”
when the processor is powered.
The current (source or sink) by any
output should be limited to a maximum of 15mA.
One important point: normally,
when idle the serial terminal is at a
logic one. When a character is sent,
the lead is brought low for 1/2400 secs
(start bit) followed by the data bits.
However, when the PICAXE is
booted, the output is initially at a high
impedance and is then brought to an
output logic zero.
Thus, prior to executing the first
SerOut instruction, it is important to
bring the output to a logic one and
pause briefly.
SC
Where from, how much?
This project was designed by Oatley Electronics who hold the copyright
on the circuit and PC board design.
A complete kit of parts, (Cat K221) which includes the PC board and all
on-board components (but NOT an LCD) is available from Oatley for $20.00.
As a special offer to SILICON CHIP readers, Oatley will include a DL6 backlit LCD
(16x2), normally selling for $12.00, for $10.00 extra.
Contact Oatley Electronics on (02) 9584 3563 or via their website:
www.oatleye.com
siliconchip.com.au
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www.ozitronics.com
Tel: (03) 9434 3806 Fax: (03) 9011 6220
Email: sales2005<at>ozitronics.com
Rolling Code 2-channel UHF Remote
Momentary or latching relays
with indicator LEDs. Range up
to 25m. Up to 15 Tx's can be
learnt by one Rx. 12VDC.
K157 - $71.50
Also available assembled K157A...... $88.00
4-Channel version (kit) K180 ...............$82.50
10-Channel version (kit) K181 .............$99.00
2-button remote for K157 .................$23.10
4-button remote for K180/1 ..............$25.85
Prices include GST – shipping extra.
Full documentation available from website.
Silicon Chip
Binders
REAL
VALUE
AT
$12.95
PLUS P
&
P
H SILICON CHIP logo printed in
gold-coloured lettering on spine
& cover
H Buy five and get them postage
free!
Price: $A12.95 plus $A7.00 p&p per
oder. Available only in Australia.
Just fill in the handy order form
in this issue; or fax (02) 9979
6503; or ring (02) 9979 5644 &
quote your credit card number.
August 2005 81
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