This is only a preview of the February 2020 issue of Practical Electronics. You can view 0 of the 80 pages in the full issue. Articles in this series:
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Max’s Cool Beans
By Max the Magnificent
The wanters, the wishers, and the makers!
don’t see those everyday), the Arduino
was announced, MAKE magazine was
launched, and the Maker Movement was
born. These days it’s hard to swing a stick
without hitting a maker (not that this is
a practice I advocate, you understand).
Now I have friends (one day I’ll tell
them). One of the great things about what
I do – freelance technical consulting and
writing – is that I get to meet a lot of interesting folks, including magnificent makers.
In my previous column I introduced you
to the aptly named Nick Bild in the US.
In this column, I’d like you to say ‘Hello’
to Richard Grafton in the UK (Fig.1.). The
following is in Richard’s own words.
Say hi to Richard Grafton
Fig.1. Richard Grafton flaunting a cheesy smile to go with his breadboard computer.
H
ere’s a quote close to my
heart: “Three categories of people
exist in the world; ‘the wanters’,
‘the wishers’, and ‘the makers’.” (101
Keys to Everyday Passion by Israelmore
Ayivor, see: https://amzn.to/2R2JfGq).
I’ve been making things for as long
as I can remember. Some of them even
worked. I only wish we’d had the Internet or someone to mentor me when I was
a kid; my dear old dad was hard pushed
to replace a fuse. One Christmas, when I
was about 10 years old, my parents gave
me one of those electronics kits that involved a lot of springs – a simpler version of the ‘Electronic Playground and
Learning Center’ I just found on Amazon
(https://amzn.to/2QVxLEM). It also came
with a book that talked about things like
‘resistor bridges,’ which made no sense
whatsoever to my uninformed brain. Lacking someone to guide me, I’m surprised
I survived the experience.
By the time I was 12, my parents had
taken out subscriptions to Practical Electronics and Practical Wireless magazines.
I hoarded my pocket money (allowance),
and at the beginning of each month I’d
keep popping into the newsagent at the
bottom of the road on the way home
from school to see if either of these magazines had arrived. As soon as I had one
Practical Electronics | February | 2020
in my sweaty hands, I would sit on the
wall outside the newsagents reading it.
If there was a simple project (typically something that made a lot of noise)
that looked interesting and was within
my budget, I‘d hop on a bus and go to
a dingy backstreet electronics components store called Bardwells (http://bit.
ly/pe-feb20-bdwls), purchase all of the
bits and pieces, then return home and
disappear into my bedroom for a few
hours until – eventually – strange and
annoying sounds would ensue.
A lot of my friends at that time made
‘stuff.’ I thought making things was a
common practice. The 1970s were the
heyday of the Heathkit when it was cheaper to build something than to buy it, and
there were little TV and Radio repair shops
all over the place. Then things started to
change. It became cheaper to buy things
than to build them, and easier to replace
something than to fix it. Companies making
electronic kits started to close down, DIY
magazines started to disappear from the
newsagent’s shelves, and people in general
seemed to lose interest in making things.
I was sad. I thought I was all alone. A
little tear rolled down my cheek. I tried
to be brave.
Then, suddenly, circa 2005, with a
fanfare of metaphorical trumpets (you
I suppose I’ve been a ‘maker’ all my life. I
remember from a very early age inventing
things that popped into my imagination
– usually with Lego Technic or anything
around the house I could get my hands
on. At around the age of 14, I recall finding a book introducing Visual Basic 5
(complete with the software on CD). My
curiosity got the better of me; I fired up
Windows 95 and started playing with it.
Somehow, I intuitively understood what
it was all about, and realised I could actually ‘make’ stuff using a computer.
Of course, this opened up a whole
world of exciting possibilities. My crowning glory was writing a (pretty crude) encrypted messaging program which I distributed to my school friends on floppy
disks (marked ‘Maths Homework’) so we
could chat over the school’s computer network without being detected. It worked
pretty well too! I suppose this was when
I got excited about making stuff that other
people could use.
All this fun culminated in me doing
an interdisciplinary informatics and
engineering degree at the University of
Sussex (which I loved from beginning to
end). At the time, I was often surprised
to find out that I already knew parts of
the computing curriculum because I’d
already self-discovered the algorithm
or design principle through my Visual
Basic tinkering – I just hadn’t considered at 14 that there’d already be names
for these things or that I’d have to rehash
my early software discoveries later on in
life to pass exams!
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This seed of inspiration is how I ended up tinkering away on a kitchen table late into the evening
over a period of several weeks. What emerged was
a humble 4-bit arithmetic unit designed using 7400
series integrated circuits – you can think of it as a
simple binary calculator. This was the embryo of the
first ARITH-MATIC product: the S1-AU Mk1 (Fig.2.).
As a self-confessed geek this was all great fun for
me, but according to my partner it was not sustainable to hog the kitchen table! To avoid any inevitable conflict, I moved the project into a shared studio
space and slowly developed a series of prototypes.
After quite a few redesigns and failures, what emerged
were three DIY electronic kits that dissect the complex mechanisms of computation.
I had learnt so much over this period of time
and undertaken so much R&D that I realised this
Fig.2. The S1-AU Mk1 4-bit arithmetic unit.
After my time at Sussex, I decided to go into research so I could continue making stuff. I then spent two years training at BBC R&D (learning
how to do all this engineering stuff properly). It was a real privilege to
be surrounded by so many talented people; also, being able to design
things that could make a huge impact really set my life in motion as a
technologist before moving into more senior roles in the tech industry.
Now, more than 20 years on from that fateful encounter with Visual
Basic 5, I’m still doing exactly what I was doing at 14 – thinking about
how I can make something and then willing it into existence. I blame
it all on that Visual Basic book, which is still sitting on my bookshelf.
More recently, however, I’ve begun to explore the world beyond software, and my inspiration for making things has turned towards what
has been, rather than what is yet to come.
I think this is important, because software as a medium is always a
losing battle against entropy – as soon as you write something it exists
for a fleeting moment before it starts its enviable decay towards obsolescence. As a reaction to this, I’ve started to take more of an interest
in hardware, as it seems to have a longer shelf life. But, most importantly, I’ve rediscovered the physical beauty of hardware, and – to
me – the more (seemingly) archaic the better!
Recently, I’ve found myself becoming increasingly interested in
early(ish) computing machines and hardware such as the PDP-8.
This is not only because it’s beautiful, but because you can actually see what’s going on – the computing isn’t hidden away on a
piece of silicon or in the compiler.
This idea is exciting to me as a maker because it has reopened
a whole new world and reignited my imagination for creating –
leading to the genesis of my ARITH-MATIC project.
ARITH-MATIC
The story starts back in 2016 when I decided to make a serendipitous trip to the brilliant Museum of Computing in Swindon. This is a rather odd place, hidden away in an unassuming precinct in the town centre, packed full of vintage and
retro computing devices from mechanical calculators to early
personal computers and classic gaming consoles. I love it.
After wandering around for a few hours, I was struck by two
things: the aesthetic beauty of early mechanical calculators
and the DIY spirit of the early micro-computer hobbyist kits
– especially the Acorn System 1 (1979) and the Science of
Cambridge Mk14 (1977). You can call it nostalgia, but there
is something I love about these computational devices – how
basic and tactile they are, unlike the shiny and polished
devices we all carry in our pockets today.
Inspired by the pioneering spirit of DIY electronics
and the aesthetic beauty of mechanical calculators, I decided to design my own computational device. This would not only
capture the archaic beauty of vintage computing, but also dissect the
computational mechanisms that operate at the heart of these machines.
60
Fig.3. The 4-bit Cambrige-1 breadboard computer.
Practical Electronics | February | 2020
wasn’t really a personal project anymore.
I’d taught myself new EDA (electronic
design automation) tools, built relationships with PCB manufacturers, opened
accounts with electronic component suppliers, captured user-centred feedback
from other makers and design engineers,
grown a trusted network of freelance support, registered a domain name and was
working from a studio. Whether I liked
it or not I was actually a micro startup!
At this point things got serious – I was
ready to launch. This part, of course, is a
whole other story in itself, but I’m pleased
to say that – since that time – the S1-AU
has found its way into the hands of many
more individuals than I could have ever
imagined. Enabling pragmatic makers,
hobbyists, and enthusiasts to explore
the guts of computing in a hands-on and
practical way. And, that’s a really exciting prospect for a project that started life
on a kitchen table.
Back to me (Max)
OK, back to me – Max – again. I have
to say that I love the aesthetics of Richard’s work in the form of his black circuit
boards combined with red LEDs and red
tactile momentary pushbutton switches. I also appreciate the way he aligns
all of his resistors the same way round,
which is just the way I would do it (can
you spell ‘obsessive compulsive’?). You
can discover more about Richard’s kits
at: https://arith-matic.com/
As I mentioned in my Cool Beans
column in August 2019, I bounce back
to England a couple of times a year to
visit my dear old mom. On the last Friday
before I return to America, a gaggle (an
appropriate word to use as a collective
noun in this case, I think) of my technogeek chums travel from around the country to congregate at my brother’s house.
We spend the day showing off our latest
and greatest creations while my mother
provides appropriate ‘Ooh’ and ‘Aah’
sound effects, as and when required.
Well, on my next visit, Richard has
promised to join our merry throng. In addition to his temptingly tasty ARITH-MATIC boards, I’m hoping he will also dazzle
us with his 4-bit breadboard computer,
which he calls the Cambrige-1 (Fig.3.)
As Richard says: ‘The Cambridge-1 is a
4-bit 7400-series-based CPU that features
a 4-bit word size, blinkenlights-a-plenty,
and some (slightly naughty) Arduinobased cheating to virtualise the control
unit. It also contains an 8-bit data and address bus with some instruction set tricks
to perform 8-bit operations as well. All of
this at a whopping clock speed of 40Hz.’
Richard designed and built the Cambridge-1 to take to the 2019 Retro Computer Festival (http://bit.ly/34r1SYN),
which was held the Museum of Computing in Cambridge. You can see a video
of this little rascal running (the Cambridge-1, not Richard) on YouTube (http://
bit.ly/2OT2FuG). Also, you can read more
about its creation on Richard’s website
(http://bit.ly/34trxjA), and you can delve
into the nitty-gritty details on Richard’s
GitHub page (http://bit.ly/2OPU4cl).
Well, that’s it for this Cool Beans
column. I have so much to say, but I can
almost feel the editor leaning over my
shoulder and saying, ‘How many words?’.
The problem is that, much like my dear
old mum, the real trick is to get me to
stop waffling. And so, until next time,
have a good one!
Cool bean Max Maxfield (Hawaiian shirt, on the right) is emperor
of all he surveys at CliveMaxfield.com – the go-to site for the
latest and greatest in technological geekdom.
Comments or questions? Email Max at: max<at>CliveMaxfield.com
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