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Ed S
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Ed S
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Just a plug for a relevant community! Book posts are welcome here in Retro Computing and also over at the Computer History Book Club. If you like reading about computer history, you'll be pleased to see Jimmy Maher has collected his excellent blog posts into free ebooks organised chronologically at
http://www.filfre.net/the-digital-antiquarian-e-book-library/
which will be great for offline reading.
Computer History Book Club
I've read this old computer book and I like it
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Ed S's profile photoKam-Yung Soh's profile photo
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If you enjoy Jimmy Maher's posts, you can also support him directly via Pateron [ https://www.patreon.com/DigitalAntiquarian ].
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Ed S
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Early computing in the Netherlands - before ZEBRA, there was ARRA II, and before that, there was ARRA - which was certainly seen working, once! (These were difficult post-war years, and there's a feeling here of the spirit of reconstruction and invention.)

Extracts from a timeline:
"""
1952 The presentation of the ARRA at the MC, a milestone in Dutch computer-building. This relay machine was hailed as a symbol of faith in technology in the post-war reconstruction period. Proved to be practically unusable.
1952 Dijkstra started work at the MC as the first programmer in the Netherlands and one of the first of the world.
1953 Van der Poel develops the PTERA, the first computer in the Netherlands with radio tubes instead of relays.
1954 ARRA II developed by Blauw at MC; unlike ARRA I, successful.. Radio tubes and transistors. Used for: technical and scientific calculation.
"""
- https://web.archive.org/web/20160102191809/http://dutch-computer-heritage.com/DUTCH_COMPUTER_HISTORY_3_Timeline.htm
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Peter Walker's profile photoJan van den Broek's profile photo
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Fascinating
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This weekend, launch of the amateur rocket Nexø-1 - another step on the path to put a person into space using only alcohol and liquid oxygen.
Dear readers Let’s get the most important news out in the open immediately – The Vostoks diesel tank is repaired and ready to use! Monday evening, we will take a look at the weather forecast and into each other’s eyes and then we’ll make a Go/NoGo decision for the upcoming weekend. Phew it is so …
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Kam-Yung Soh's profile photoPeter Walker's profile photoEd S's profile photo
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And from the other side of the pond, +Peter Walker, the first chapter of
https://www.goodreads.com/book/show/1331484.Backroom_Boys
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Zilog would have you believe the Z80 was a massive improvement on the 8080. And they are probably right. But for the Game Boy Nintendo used neither of them - instead, a custom CPU with many extras relative to an 8080, and some things missing (and other things added) relative to a Z80. See also the comparison at
http://verhoeven272.nl/cgi-bin/FS?fruttenboel%2FGameboy&Gameboy+section&GBtop&GBsummary&GBcontent
and for heaps of implementation details on the Z80 - including the 4-bit ALU and the clever register bank swapping, see +Ken Shirriff's blog starting perhaps with
http://www.righto.com/2013/09/the-z-80-has-4-bit-alu-heres-how-it.html
INTRODUCTION The Game Boy’s CPU is a hybrid between the Intel 8080 and the Zilog Z80. In this post we’ll investigate the foundations of this custom microprocessor.
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Fabrice Lété's profile photoFred Beckhusen (aka Ferd Frederix)'s profile photoEd S's profile photo
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Great story - and thanks for the link to that oral history. The story of anti-copy traps and gotchas is a very interesting one - especially as we are now trying to recapture layout for purposes of simulation in the browser, and we hit the same traps!
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This is why we can't have nice things... all free apps should be built for prehistoric versions of the OS, by law! Fortunately I could go to
http://ashleyf.github.io/HP35/
to get some relief.
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It all depends on the market you have, when you sold a $2 game to ten thousand customers, if you estimate the next update will break 5% of the installed base, but that 99% of those players are done with the game, you can't afford worrying about the few casualties.
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Nuclear power - in SPAAACE! TIL there are some 30 nuclear reactors in orbit - Russian ones, although the one shown here is American. Cooled by liquid metal, capable of producing 2kW of electricity for 250 years - but producing ten times as much waste heat, so most of the volume if not the weight is radiators to get rid of the heat. The core itself masses something over 50kg, about as much as a sack of potatoes.

For NASA, it turns out the negative publicity of nuclear power makes solar power more attractive - even for Juno, as far from the Sun as Jupiter. It also turns out that insurance for a nuclear launch costs as much as the Plutonium, and that's not exactly inexpensive.

See also
https://en.wikipedia.org/wiki/TOPAZ_nuclear_reactor

via this presentation on the subject:
https://docs.google.com/viewer?url=http://spirit.as.utexas.edu/~fiso/telecon/McNutt_4-16-14/McNutt_4-16-14.ppt

via the Space Exploration stackoverflow at
http://space.stackexchange.com/questions/17047
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Isaac Kuo's profile photoChris Gallaty's profile photoChris McClelland's profile photo
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I always thought actual reactors (i.e with fissile material, U-235 or Pu-239) in orbit were banned by one of the nuclear non-proliferation treaties.

One learns new things every day, evidently.
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Ed S

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Can you tell your wulst from your tectum? An interesting read.
"300 million years of reptilian, avian, and mammalian evolution have allowed the self-model and the social model to evolve in tandem, each influencing the other. We understand other people by projecting ourselves onto them. But we also understand ourselves by considering the way other people might see us. Data from my own lab suggests that the cortical networks in the human brain that allow us to attribute consciousness to others overlap extensively with the networks that construct our own sense of consciousness."
A neuroscientist on how we came to be aware of ourselves.
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Strange loops! I'm sure other-representation, and self-representation, and representation of others' representation of self are all involved.
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"if you look at it carefully you'll see all the 5 'hot' burns the Falcon 9 has performed on this CRS-9 mission, in a single picture - and I believe it's also showing something new, the 'RCS burn' of the 'quick flip' of the first stage:
- The ascent burn of the 9 Merlin-1D engines: the long bright arc upwards,
- the single Merlin-1D-Vac second stage burn: the thin, short line starting after the short pause of MECO,
- the 3-engine 'boostback burn' of the first stage, the upwards arcing thin 'fish hook' part that is overlaid with the thin second stage arc - which sent the first stage on a return trajectory towards Landing Zone 1. This is barely visible but it's there.
- the ~15 seconds of the 3-engine 're-entry burn' of the first stage at an altitude of about 50 miles: the topmost bright vertical line, above the ascent arc,
- and the final 1-engine 'landing burn' of the first stage: the lowest bright vertical line ending at the landing pad!
And if you zoom in really, really close you might be able to see a 'smudge' right before the 'fish hook' separation point: I believe that smudge is showing the cold-RCS thruster exhaust as the first stage performed its 'quick flip', the nitrogen gas exhaust lit by the departing second stage's exhaust."
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"The BBC understands that Softbank will commit to doubling the size of ARM's UK workforce over the next five years" doesn't sound so bad over the short term. In the longer term of course it could be bad - NVIDIA pulled out of the UK, as did STM. Broadcom are still here.

via +Kam-Yung Soh 
ARM Holdings, one of the UK's biggest technology companies, is set to announce it is being bought by Japan's Softbank for £24bn ($32bn).
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Johan Steenkamp's profile photoKam-Yung Soh's profile photoYoshio Akiyama's profile photoEd S's profile photo
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Maybe, +Kam-Yung Soh, "sold" is the wrong verb, but ARM do get an average of 5 cents per ARM CPU shipped - and that's just the royalties, about 60% of their revenue. The rest is licensing fees, which is from people who want the right to design or make or ship ARM CPUs. Here's an interesting article:
http://www.anandtech.com/show/7112/the-arm-diaries-part-1-how-arms-business-model-works/2
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Ed S
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It seems the outfit who wrote the Pokemon Go app were a little too closely associated with Google, and somehow used an authentication path intended for Chrome, which was capable of getting full account access. But it probably never did.
"""
- Undocumented parts of auth flow are bad, and can lead to problems like this ambiguity
- The direct token that Niantic gets can't access the gmail api / gcal api
- This token is overpermed, due to the https://www.google.com/accounts/OAuthLogin scope
"""
- from the textual explanation at
https://gist.github.com/arirubinstein/fd5453537436a8757266f908c3e41538

See also a sort of announcement but-not-apology at
https://support.pokemongo.nianticlabs.com/hc/en-us/articles/222648408-Permissions-update
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Ed S
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Can't get enough time on the mainframe? Get yourself a scientific workstation! Specifically, get Acorn's 32 bit workstation, based on the new CPU from National Semiconductor, the NS32016. This might be the last 32 bit system you'll need - and for just £3500 or so.
Now, it's not entirely unlike a BBC Micro with a 32016 coprocessor, and you might previously have met this Acorn Cambridge Workstation in its previous incarnation, as an Acorn Business Computer, the ABC210.
More info about the ABC210 at
http://www.computinghistory.org.uk/det/33101/Acorn-Cambridge-Workstation/
and about the Cambridge Workstation at
http://chrisacorns.computinghistory.org.uk/Computers/ACW.html
and much much more detail on the NS32016 at
http://cpu-ns32k.net/
including details of a modern rework for FPGA - also ready to hook up to your BBC Micro, assuming you still have it.
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mathew murphy's profile photoEd S's profile photoChris McClelland's profile photo
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One real problem with the Amiga was that the disk control logic was highly programmable, and some games companies used this programmability to implement copy-protection, by taking the drive out of spec. Frequent such out-of-spec episodes obviously caused wear on the drive, or pushed the head out of alignment or whatever.
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Ed S

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It's my fifth birthday on G+ - so here's five things I got in the last five years. Can you spot the odd one out? (Actually, each one is odd in its own special way.)
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Let's suppose it's the platform!
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