This is only a preview of the March 1998 issue of Silicon Chip. You can view 43 of the 96 pages in the full issue, including the advertisments. For full access, purchase the issue for $10.00 or subscribe for access to the latest issues. Articles in this series:
Items relevant to "Sustain Unit For Electric Guitars":
Items relevant to "Multi-Purpose Fast Battery Charger; Pt.2":
Items relevant to "Command Control For Model Railways; Pt.3":
Items relevant to "PC-Controlled Liquid Crystal Display Board":
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PRODUCT SHOWCASE
New mains filters with
metallic flange
Schaffner has released the FN 9226
series IEC mains filter modules. They
are very compact, measuring 30.4 x
22.9mm and have a depth of only
22.9mm, making them suitable for a
wide range of applications including
computers, office automation equip
ment and medical apparatus (a class B
version caters for low leakage current
requirements).
The filters have a metal flange, al
lowing them to be mounted directly
onto the internal face of equipment
panels, eliminating panel pre-assem
bly operations as needed for most
IEC inlet filters. There is a choice of
connections: PCB-mount, Fast-On or
solder lug.
The FN 9226 series filters are IEC
950 compliant. They have a maximum
operating voltage of 250VAC, current
ratings of 1, 3, 6 or 10A, and an operat
ing frequency range from DC to 400Hz.
For further information, contact
Westek Industrial Products Pty Ltd,
Unit 2, 6-10 Maria St, Laverton North,
Vic 3026. Phone (03) 9369 8802; fax
(03) 9369 8006.
Low voltage amplifier
delivers 1.5W
Analog Devices Inc have released
the SSM2211 which delivers up to
1.5W RMS into a 4Ω load and 1W
into an 8Ω load. It employs a single
supply of 2.7V to 5.5V and provides
a rail-to-rail differential output.
With its 4MHz bandwidth, the
SSM2211 provides a flat response
across the entire audio spectrum.
Nor does it need any external heat
sink to deliver its 1W output into
a 8Ω load.
At full power, harmonic distortion
is quoted at 0.2% and at 500mW,
distortion is less than 0.1%. Quies
cent current is 8.5mA and in standby
mode it consumes less than 100nA.
With a 5V supply, the power sup
ply rejection ratio (PSRR) is better
than 65dB (from 4.75V to 5.25V).
It comes in an 8-pin DIP or SO-8
surface mount packages.
For further information on the
SSM2211 low-voltage amplifier,
contact Hartec, 205A Middlebor
ough Road, Box Hill, Vic 3128.
Phone 1 800 335 623.
New technical standard released by the
Australian Communications Authority
According to a recent press
release, the Australian Commu
nications Authority has ushered
in a major milestone with the
release of new technical stand
ards for customer equipment
and cabling. These former Austel
standards have been significantly
revised and updated to reflect the
intentions of the Telecommuni
cations Act 1997 for a more open
and freer marketplace.
Unlike before, the new Telecom
munications Act only empowers
the ACA to adopt standards based
on four specific criteria: for the
protection of personal health and
safety, network integrity, and to
ensure inter-operability and ac
cess to emergency services.
70 Silicon Chip
As a result, the 30-odd previous
Austel technical standards have
now been rewritten and reduced
to just 21 to reflect this limited
scope.
In line with the Government’s
policy of industry self-regulation,
the old Austel technical standards
were revised by working groups
of the Australian Communica
tions Industry Forum, in cooper
ation with Standards Australia.
Standards Australia Technical
Committee IT/17 was responsible
for rewriting the ACA Standard
TS008 dealing with cabling.
Roger Lyle, Standards Austral
ia’s Associate Director for Com
munications Technologies, says
the standards had to be revised
by 31st December, 1997 otherwise
they would have lapsed.
“That gave the industry only
a few months to actually review
and rewrite them.” Mr Lyle said.
“It’s a credit to the industry that it
was able to respond and get them
out within such strict time con
straints. To ensure compliance
with the new regulatory regime,
it’s vital that users of the old
Austel Technical Standards now
obtain copies of the new ACA
Technical Standards”.
The new standards can be
purchased at Standards Australia
sales offices and agencies in all
state capitals or by phoning the
Customer Service Centre on 1300
654 646.
Wooden you like
a new TV?
German television manufacturer
Dual has released a range of luxury
TV sets with the rather unusual fea
ture of genuine timber cabinets. This
could be a refreshing change from the
unremitting charcoal or black plastic
cabinets used for virtually all TVs
these days.
Three models, known as the “Clas
sique Range”, are available and they
are finished in Mahogany or Oak.
A matching stand/cabinet, also in
mahogany or oak timber finish, is
available as an option.
Each set features a “Blackline S”
picture tube and a digi
tal chassis
to ensure the best possible picture.
All signals are processed in the dig
ital domain, preventing unwanted
interference degrading the original
signal. A digital chassis also allows
many convenience and performance
features not possible in analog-only
sets. In addition, the sets are mul
ti-system, allowing the playback of
video material from overseas.
The model TVM-7050M also fea
tures picture-in-picture (PIP) which
allows the viewer to watch a dif
ferent TV channel or another video
source on a small inset section of the
screen while watching their preferred
program on the main screen. This
requires the use of an external video
source such as a video recorder.
All three sets have Teletext and the
“Joy-Jog” remote control which has
only six buttons and a jog dial. An
on-screen menu shows the various
functions.
The Classique range is part of a
complete line-up of Dual TV sets
ranging in price from $1699 up to the
85cm set at $3499. Dual TV sets are
available from selected stores around
Australia. For further information,
contact Scan Audio Pty Ltd on 1 800
700 708; fax (03) 9429 9309.
ACN 073 916 686
NORBITON SYSTEMS
NS_PC101 card for XT/AT/PCs
allows access to 48 I/O lines.
There are 5 groups (0 to 4)
available on a de-facto industrial
standard 50-way ribbon cable
used in STEbus and VMEbus
19" rack mount control systems.
The board uses 2 x 8255 ICs.
Multiple boards can be used if
more I/O lines are required.
NS_LED PCB gives visual
access to five groups (0 to 4) of
the NS_PC1OX. There is a total
of 40 status LEDs. The board
offers a 25-way “D” type female
socket. The lines are driven by
74244 ICs & configured as a
parallel printer port. This socket
gives access to printer port kits,
eg, stepper motors, LCDs, direct
digital synthesis.
NS_16_8 PCB is a system conditioning card with 16 optically
isolated inputs set-up for either
12V or 24V operation. The board
provides 8 single pole, double
throw relays with 10 Amp contact rating.
KITS & CARDS
NS_DC_DC is a step down
converter with an input range
11 to 35V DC and an output of
5 volts DC at 5 Amps, with an
output ripple of approx 150mV.
There is an IN/OUT 50-way
connector isolating the 5V and
12V+ & 12V- rails of the PC
power supply. This segregates
PC’s power when working on
prototypes.
NSDC_DC1 module used with
NS_DC_DC & NSDC_DC4
converters is a 5V to 12V(+/-)
step- up converter. The board
utilises 743 switch mode IC with
2 x 12V regulators, with output
ripple of approx 200mV.
NS_UTIL1 prototyping board
has 1580 bread board holes access to any 3 groups (0 to 4) on
the 50-way cable pinout. Power
is available from the 50-way
cable format 5 volts at 2 Amps
& 12V+ 12V- at 1 Amp. There
is provision for array resistors
with either a ground or positive
common connection.
For brochure write to: Reply Paid 68, NORBITON SYSTEMS, PO Box 687, Rockingham WA 6968
Email: norbiton<at>bigpond.com
embedded
computers designed for the real world
Put some intelligence in your next project!
MC112 - 68HC11 processor, 32k RAM,
32k EPROM, serial, parallel, timers, A/D
converters, BUFFALO software with
inbuilt assembler / disassembler and bootloader. $220
Postage and handling $10.
Available soon - ARM-based RISC, DSP and PIC systems
• RISC
• DSP
• Parallel
• Microcontrollers
• Ultra low power
• High Performance
• Data Acquisition
• Control Systems
• Neuro-fuzzy
• 8, 16, 32 and 64 bit
WE
HAVE
THE
SOLUTION
Embedded Pty Ltd
Level 5
371 Queen St
Brisbane
GPO Box 2603
Brisbane 4001
Phone:
Fax:
(07) 3236 5977
(07) 3221 0549
March 1998 71
A 68HC11-Based
Embedded Computer
When most people think of a computer
system, they think of a PC. But the most
common form of a computer system is the
embedded or dedicated computer. Everyone
has embedded computers built into their TV,
VCR, microwave oven and so on.
By JOHN CATSOULIS
Embedded Pty Ltd designs and
manufactures embedded computer
systems for industrial, scientific and
consumer applications. Their work
horse is the MC112, which is based
on the Motorola 68HC11. It’s easy
to program and has lots of features.
Embedded Pty Ltd has been
approached many times by elec
tronics hobbyists wanting a simple
controller for some project on which
they were working. Typically, they
were looking for a small, 8-bit mi
crocontroller with EPROM, static
RAM, parallel I/O and often analog
inputs as well. Since such systems
Multimedia projector
does not need a PC
Mitsubishi Electric has launched
their LVP-X100A Multimedia Data/
Video LCD Projector which can run
computer-based presentations with
out a computer. Its built-in PCMCIA
(Flash Memory) card driver means
the projector is self-contained.
Software is supplied to enable pres
entation contents to be downloaded
onto a PC card which slots into the
projector.
The remote control unit allows
full control of the projector as well
as providing an IR beam pointer
for cursor control of the on-screen
menu or for smooth writing and
72 Silicon Chip
just aren’t available through the
larger electronics retail chains,
Embedded have decided to give
away the design of their MC112
computer for non-commercial use,
so that anyone can build their own
embedded microcontroller.
The MC112 is a small comput
er system based on the Motorola
68HC11 microcontroller (MCU). In
addition to the “standard features”
of the MC6800 family, the 68HC11
has a 16-bit timer with four stage
programmable prescaler, a serial
communications interface (SCI), an
8-bit pulse-accumulator, real-time
drawing. You can enlarge segments
of your presentation to show detail
during the show, or use the Pic
ture-in-Picture function to display
a second picture (data or video) on
screen at the same time. The LVPX100E has six inputs, for two PCs,
two video inputs and two PC cards.
The picture size is 51cm to 762cm
diagonal and contrast ratio is 200:1.
Electronically controlled zoom,
focus and keystone correction are
also available.
For further information, contact
Mitsubishi Electric Austra
lia Pty
Ltd, 348 Victoria Rd, Rydalmere
2116. Phone (02) 9684 7777; fax (02)
9898 0484. Internet address: www.
mitsubishi-electric.com.au
interrupts, 256 bytes of static RAM,
an 8-channel analog-to-digital con
verter and onboard EEPROM.
The MC112 also has a 32K
EPROM and a 32K static RAM.
32K may not sound like a lot but
in embedded applications, it’s
huge. If you were using the MC112
to record 8-bit temperature values
from a sensor once every 30 min
utes, 32K corresponds to 1.8 years
worth of data!
The MC112 also has an optional
MC68HC24 Port Replacement Unit
(PRU) for additional parallel I/O.
With the MC112, you get up to 32
parallel I/O lines or 16 parallel I/O
plus 8 analog input channels and 8
timer channels. The MC112 meas
ures just 65 x 90 mm (small enough
to be included inside an electronics
project) and runs from 5V DC. Its
block diagram is shown in Fig.1.
For those who would rather
buy than build, the MC112 will be
available as a complete unit from
Embedded Pty Ltd. As sup
plied
by Embedded, the MC112 will in
Register of Year 2000
compliant software
Many businesses have done nothing
to ensure that their software will have
no problems when the clock ticks over
to the year 2000. Now at least there
is a register of Year 2000 com-pliant
products and organisations, launched
by Standards Australia and the Aus
tralian Computer Society.
The register of compliant products
can be accessed free of charge through
Standards Australia’s web site at www.
standards.com.au or directly at www.
y2kregister.com.au
The site provides a comprehensive
list of Year 2000 compliant software
and hardware products in Australia
and New Zealand, as defined by the
Standards Australia publication SAA/
clude the public-domain BUFFALO
monitor software in its EPROM.
This includes an inbuilt assembler
which allows you to enter and run
machine code and/or assembly
language programs directly and to
examine the contents of memory
and the processor’s registers.
BUFFALO also provides a set of
software tools to make the program
mer’s life easier. These subroutines
include facilities for printing to the
screen, reading from a keyboard,
and so forth.
The address and data buses of
the 68HC11 are multiplexed and
demultiplexing is achieved using
a 74HCT573 octal latch (U4). The
address strobe, ~AS, causes the
74HCT573 to latch and hold the
low-order address lines at the start
of the memory cycle. The interrupt
lines (~IRQ and ~XIRQ) and ~RE
SNZ MP77:1998, “A Definition of Year
2000 Requirements”.
Non-compliant products generally
depend on the date being represented
by only two digits and when 2000
rolls around, they may interpret the
“00” in the “2000” as “1900”, causing
anything from wrong data entry to total
system failure.
Visitors to the web site can obtain
further information about the com
pliance of a product or a vendor by
clicking on the name of the organisa
tions listed on the register. Hyper links
then take the visitor to the vendor’s
home page.
Vendors pay a one-time registration
fee for entry into the register and a fee
for each product. The register will be
updated each week.
Note that none of the products in
SET have 4.7kΩ pull-up
resistors. The MC112 also
has a Low Voltage Inhibitor
(LVI), MC34064, for gener
ating a power-on reset. The
LVI looks like a transistor
and provides an active-low
reset whenever power falls
below a preset value. Thus,
when power is applied to
the MC112, the LVI holds
the system reset until it is
stabilised.
Port D is the serial inter
face, with bit 0 as the receive
data input and bit 1 as the transmit
data output. The Tx and Rx lines
are converted to RS232 levels by a
MAX202 (U2). This is to allow the
connection of the MC112 to a sim
ple terminal or PC. The MC68HC11
has an onboard 8-channel, 8-bit
ADC. This is made available to the
user through a 16-pin IDC header
labelled PORTE on the PC board.
This may also be configured as a
general-purpose digital I/O port
under software control.
The MC112 is available as a
complete unit, including ROM pre
programmed with BUFFALO, user’s
guide and cables, for $250. Postage
and handling is $10.
For further information, contact
Embedded Pty Ltd, GPO Box 2603,
Brisbane, Qld 4001. Phone (07) 3236
5977; fax (07) 3221 0549.
the register have been independently
tested for year 2000 compliance. The
vendors must sign a self-declaration,
declaring the products in question are
year 2000 compliant, before they can
be listed on the register.
Low-cost laser
diode module
Oatley Electronics have a new laser
diode module which has automatic
power control (APC) circuitry but its
PC board is much smaller than previ
ous modules. The finished assembly is
44mm long and would fit into a tube
with an internal diameter of 15mm. It
requires 3-5V DC at about 45mA. Its
output is 5mW at 650nm.
Priced at just $20, it is available from
Oatley Electronics, PO Box 89, Oatley,
STEPDOWN
TRANSFORMERS
60VA to 3KVA encased toroids
Harbuch Electronics Pty Ltd
9/40 Leighton Pl. HORNSBY 2077
Ph (02) 9476-5854 Fx (02) 9476-3231
NSW 2223. Phone (02) 9584 3563; fax
(02) 9584 3561.
Large LCD clock
is easy to see
How many
times have you
wished for a
digital clock
that you could
see from a rea
sonable dis
tance across
the room? So
many digital
clocks have such tiny figures that only
the young and those with super acute
vision can see them to tell the time.
Now here is a clock which you really
can see from a good distance. Its digits
are no less than 65mm high and even
this relatively middle-aged writer has
no trouble seeing the time of day from a
distance of more than 20 metres away.
The clock can be set to display 12
or 24-hour time and has three minor
displays, with 18mm high digits, for
the date (day and month), day (eg,
SAT) and the temperature in Celsius
or Fahrenheit.
It runs on two AAA cells and can
be wall hung. Its overall dimensions
are 210mm wide, 230mm high and
maximum depth is 30mm although
the fascia is curved so that its apparent
thickness is less.
Price of this wonder-clock? Just
$89.95 from all Jaycar Electronics
stores and dealers. (Cat XC-0230).
March 1998 73
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