
Reverse engineering the ARM1, ancestor of the iPhone's processor - reportingsjr
http://www.righto.com/2015/12/reverse-engineering-arm1-ancestor-of.html
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cesarb
It's quite interesting that a lack of resources ("given the small size of the
design team at Acorn, a simple RISC chip was a practical choice") forced them
to focus on simplicity. That simplicity then helped the chip use less power,
which later left them well-positioned to capture a large share of a nascent
battery-powered market.

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erikpukinskis
Indeed! I think their open source business model had a lot to do with their
success too.

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to3m
Possibly relevant - but in any event, interesting throughout - is Sophie
Wilson's Computer History Museum interview:
[http://www.computerhistory.org/collections/catalog/102746190](http://www.computerhistory.org/collections/catalog/102746190)

~~~
guiambros
Somewhat related: Micro Men [1], a semi-documentary/drama movie about
Sinclair's rivalry against Acorn computers in late 70s and early 80s. Sophie
Wilson herself plays a quick cameo role towards the very end.

[1]
[https://www.youtube.com/watch?v=hco_Av2DJ8o](https://www.youtube.com/watch?v=hco_Av2DJ8o)

~~~
jacquesm
They never were in the same space. Sir Clive made things cheap, Acorn made
things well.

~~~
guiambros
Their stories are very interconnected, though. If Christopher Curry hadn't
worked for/with Sir Clive for 13+ years and learned about electronic
calculators, probably he would have never discovered the upcoming wave of
personal computers.

Also, it seems that Sir Clive's lack of vision for the future of computers,
and his scattered mad-inventor-turned-businessman, were the main reasons for
Cambridge Processing Unit Ltd - later Acorn Computers - being created in the
first place.

Somewhat, the supercomputer we carry in our pockets these days are a direct
consequence of Sir Clive's actions (or inactions).

~~~
jacquesm
I'll be more than happy to concede those points. It's a pity that Sir Clive
didn't have the eye for quality as much as he had one for being totally
original. Combined the two would have been deadly, the man was an absolute
visionary.

He's still around (75 now).

~~~
guiambros
Indeed. It seems he got bored too easily; sticking with one industry wasn't
satisfying enough for him.

I guess _serial entrepreneur_ would be the buzzword these days.

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moron4hire
I think it would be fascinating if some of the older fab processes could be
democratized and people could start experimenting with chip fab at home.
Perhaps some tech out of the 3D printing field would be adaptable. No, you're
not going to make something blazingly fast, but imagine printing your own
ATMEGA328P or MSP430 or even 8086 clone.

~~~
Gibbon1
I think running mixed lots of wafers is still a thing. However besides still
being very expensive the other two issues are the software tools to lay out
the chips. And then the cost of making the masks[1]. Friend of mine was
working for a startup five years ago I think he said they needed 2.5 million
for a small team + initial fab.

If you are interested you can get into programming FPGA's for a few grand at
most. Far as I can tell looking on the outside of people doing both it's
almost the same minus the chip layout manufacturing step. Also the design
cycle time is hella faster and cheaper.

[1] I have no idea what masks cost now, but 15 years ago the company I worked
for needed to change a metal mask and it cost $50k, I think a full set was
$250,000.

~~~
trsohmers
I'm the founder of a startup taping out of first test chip in May... Getting
100 chips back on a shuttle run (Also known as a multi project wafer, where
mask costs are shared by multiple companies) will cost us around $250,000.
That is just the cost of these first 100 chips. Mask costs for a modern (eg
28nm) process start at about $2 Million, and go up from there pretty quickly,
but is based on a lot of factors. Once the masks are made though, it is
roughly $5K a wafer (where you can have 100s of dies on a wafer.

~~~
elbigbad
This sounds really interesting. I don't know what too much of this means
though. Can you recommend books or in depth articles about the process of ic
making?

~~~
nickpsecurity
The Wikipedia articles on semiconductor manufacturing are pretty good. Far as
ASIC's, I struggled a while to find a great resource on all aspects of design,
verification, and prototyping. Here's the best one I found for you:

[http://cc.ee.ntu.edu.tw/~ywchang/Courses/PD/EDA_Chapter1.pdf](http://cc.ee.ntu.edu.tw/~ywchang/Courses/PD/EDA_Chapter1.pdf)

On top of that, there's the cost of the photomasks that print the samples for
testing (and later production). They range from tens of thousands on oldest
nodes to millions on newer ones. Every time you screw up and change the design
you buy another mask. Hence, avoidance of new nodes by low volume groups,
design/verification tools that can cost $1mil/yr a person, and heavy re-use of
components.

One trick that's popular is called multi-project wafers: a mask and chip run
that's shared by several people with high cost split among them. This is
available through groups like MOSIS and X-Fab. Lets you test your design in
[more] affordable pieces. Plus, tooling and overall cost has come down for
older nodes which are still highly usable for many scenarios:

[http://gsaglobal.org/forum/2009/1/articles_full_double.asp](http://gsaglobal.org/forum/2009/1/articles_full_double.asp)

Open tools are getting there slowly but not reliable or competitive enough.
Here's the only open flow I know of:

[http://opencircuitdesign.com/qflow/](http://opencircuitdesign.com/qflow/)

So, overall barrier to entry for ASIC design is expensive expertise, high-cost
of proprietary tools, and cost of masks (or MPW's). Going cheap on all these
still gives several hundred thousand for a useful design on a good node.
Simpler, single-purpose chips on oldest nodes can be less than that, though.
Here's an example:

[http://www.planetanalog.com/author.asp?section_id=526&doc_id...](http://www.planetanalog.com/author.asp?section_id=526&doc_id=559519)

Hope all this helps your understanding of the situation.

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ck2
Somewhat on topic, I wonder if Acorn makes even a penny from every smartphone
made today (at least the non-intel ones).

Because that would be a lot of pennies. A true UK success story.

~~~
FigBug
Acorn no longer exists, but ARM does charge royalties for their processor
designs. Around 1% - 2.5%. They have revenue was £795.2 in 2014, so yes, that
pennies and fractions of a penny do add up.

Edit: The cheapest ARM processor I found on Digikey is $0.35, Digikey must be
buying them for under $0.15 so that royalties would be under 3/10ths of a
cent.

~~~
smcl
Acorn _kinda_ exist but they were rebranded as Element 14 a few years back. In
a slightly interesting twist, I own an Element 14 clone of the Beaglebone
Black - which is powered by ... you guessed it, an ARM chip (built by TI). You
can actually get RISC OS (the original OS for Acorn computers) images for the
BBB -
[http://beagleboard.org/project/riscos](http://beagleboard.org/project/riscos)

~~~
rasz_pl
you are thinking about wrong element 14

acorn one was 'Element 14 Ltd', purchased by Broadcom, now Avago.

