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I expected to be off-line for two or three weeks. Unfortunately, with medical problems, legal problems, accommodation problems and financial problems, at least one month of my time has been consumed with matters unrelated to work. However, for five days per week, I'm in an environment with no television, no radio, no phone and no InterNet connection. Even with a flaky laptop which has led me to draft all text on paper, it is common for me to write more than 3000 words per day. For example, the specification for the cell networking protocol is more than 19000 words. I also have seven draft articles pending with two publications. Around this, I have:-

• Read and reviewed five science fiction novels.
• Read and reviewed one book on rocketry.
• Read one book about computer security. (Not yet reviewed.)
• Started reading one book about operational amplifiers. (Not yet reviewed.)
• Skimmed through finalists of Google's Little Box Challenge.
• Designed some power circuitry and made empirical tests.
• Read MosTek's 1976 documentation for the 6502 micro-processor.
• Skimmed through 6809 micro-processor documentation. (I'm disapointed Lance A. Leventhal's description of this architecture given his better work on the 6502 architecure and 68000 architecture.)
• Skimmed through Atmel SAM [ARM] datasheets.
• Skimmed through lists of RFCs, ASTMs, ISOs, DINs, IECs, US Military Standards, European Standards, British Standards, Russian Standards and Japanese Industrial Standards.
• Watched two episodes of Black Mirror, Season 3, Episode 5: Men Against Fire and Season 3, Episode 6: Hated In The Nation [the one with the bees]. (Not yet reviewed.)
• Watched six episides of Electric Dreams (Not yet reviewed.)
• Watched the 1975 film: Rollerball. (Not yet reviewed.)
• Watched cartoon Rainbow Magic: Return To Rainspell Island. (Not yet reviewed.)
• Caught up with various controversies, such as:-
  • Jordan Peterson.
  • James Damore.
  • The Donald Trump golf-ball meme. (That's hugely entertaining but, yeah, when Donald Trump forwarded the meme, that's closer to the film: Idiocracy than respectable senior statesman.)
  • The demise of Bell Pottinger.
  • The penatration tester who goes screw-driving (as apposed to war-driving).
  • Dove's advert which isn't racist.
  • Nivea's advert which isn't racist.
  • Harvey Weinstein's casting couch. (I am too late to get a refund for enduring a film with the alleged actress Ashley Judd?)
  • Uber.
• Got an ex-housemate addicted to Tetris.
• Obtained some medication which improves concentration.
• Exercised with mixed results.
• Walked 40km in one day. I surprised myself. However, it took about 11 days to recover.
• Obtained a huge quantity of dried noodles. (Not yet reviewed.)

From this, I have made scattered progress. Specifically:-

• It is possible to make a 6502 cell network switch with 1KB RAM but this only works if the cell size is very small and/or it has four ports or less. 2KB RAM allows 24 byte cells and eight ports. Either configuration may require 32KB ROM or more.
• I found an easy method to optimize bit matrix transpose operations simultaneously on AVR, ARM and Thumb. However, it compiles very slowly.
• I've applied the technique of defensive programming to electronics. In particular, how to make all circuitry resiliant to unexpected mains electricity without incurring significant component cost or power loss. This is helped by programming and electronics having idioms for common tasks.
• I found a reference to Dimension 404, which appears to be the SyFy Channel's counterpart to Black Mirror on NetFlix and Electric Dreams on Channel4/Amazon.
• I found that it is possible to make a Communicator Badge which transmits Ambisonic A-Format audio.
• I found that it is possible to make a Communicator Badge which works in a conference bridge and places each participant in a different position on a sound-stage.
• Atmel SAM interrupts are all bottom priority by default and therefore all interrupts are processed sequentially unless specifically configured.
• Atmel SAM privileges are present by default unless running inside an interrupt or specifically relinquished. (Obvious with hindsight but worthwhile to check.)
• Don't buy the cheapest Arduino Nano clones because they don't ship with the Arduino firmware installed. Installation requires cursory understanding of SPI, a working Arduino and use of the hateful Arduino GUI. Come back PIC. All is forgiven.
• I got 4094 logic chip output shift registers working on the first attempt.
• I have completely failed to get 4021 logic chip input shift registers working. I have also completely failed to get MCP4921 DACs working. I presume the problem is Voltage level incompatibility between 3.3V circuitry and 5V circuitry.
• An LM317 Voltage Regulator consists of a Zener diode, an operational amplifier and power transistors. An LM317 is slightly less integrated than the trusty 7805 Voltage Regulator but provides significantly more flexibility. An LM317 is typically used in an output feedback arrangement to obtain a Voltage which is a multiple of the 1.25V Zener. For example, a potential divider with 10kΩ and 27kΩ to ground provides approximately 5V. (1+3ish units of the 1.25V.) However, an LM317 also works perfectly fine with no feedback. A potential divider from the input supply provides any ratio plus 1.25 Volts. Although each device handles a maximum of 28 Volts or suchlike, a sufficiently long cascade of regulators allows any input from car battery to European mains to regulated down to 5 Volts or similar.
• Mains electricity can be rectified with a MOSFET rectifier bridge. If you're crazy enough to connect MOSFET control gates directly to mains then rectification can be acheived with two NPN MOSFETs, two PNP MOSFETs and nothing else. If you want to reduce the gate Voltage to something sane, use the potential divider idiom of resistor, Zener, Zener in reverse, resistor. This can provide something around 5 Volt relative to ground.
• I sorta understand the difference between live, neutral and ground. That's sufficient for me to stay away from it until I understand it better.
• A MOSFET with 2 Ohm resistance is problematic when V = I × R, P = I × V and P = I² × R where R = 2 Ohm and I = 6.6 Ampère. That's a lot of friction.

Random findings:-

• It was predictable that a Raspberry Pi power reservior capacitor would be problematic. However, I didn't expect one to mechanically shear. Thankfully, it was trivial to re-solder.
• I have several findings around micro-controllers, SCART, VGA and HDMI.
• USB emoticon keyboards which output seven bit ASCII have been superceded by USB emoji keyboards which provide Unicode symbols. I presume they are implemented as a USB keyboard device which sends decimal sequence code-points while a virtual AltGr key is held. I mention this because my expertise with micro-controllers is almost at a level where I could implement something similar.
• Found that a large number of US Military Standards were dropped in 2005. Although, given the level of bureaucracy, no-one is quite sure of the number before or after the purge. Some estimate that almost 1/3 were dropped for the purpose of supply chain streamlining. This includes MIL-STD-1750A which specified use of micro-processors with 16 general purpose registers and numerous other features.
• The British have a standard for the manufacture of cricket balls, BS5993, and their standard for brewing tea, BS6008, is now an international standard, ISO3103.
• Meanwhile, the Germans have, DIN4531, a standard for ViewMaster stereoscopic picture viewers.
• Crowd-funding platforms don't work unless you already have momentum or a niche like table-top rôle-playing.
• AltPwr.Net has published circuit diagrams, circuit board layouts and Arduino software which is supposedly compatible wit MQTT. Documentation is sparse.
• The efficiency of a candle can be improved with the use of a Peltier device and an LED. Peltier devices are annoying inefficient but the large heat gradient of a bare flame makes it worthwhile.
• Electric Dreams, Season 1, Episode 3: The Commuter, led me to re-read the William Gibson story: The Gernsback Continuum and that led me to re-read the Phillip K. Dick story: Piper In The Woods. I'm less impressed with William Gibson's originality but I'm mystified why Phillip K. Dick gets so much more attention than Ray Bradbury.
• I may be in the oft-derided category of tired and emotional. A large number of things make me cry for different reasons. The Gernsback Continuum made me cry because I'm not ready - we're not ready - to live in a techno-utopia. Daft Punk album: Tron Legacy, track 10: Adagio For Tron has a really haunting cello which makes me cry. Porter Robinson & Madeon's animated music video for Shelter consistently made me cry seven times out of seven. A song in Rainbow Magic: Return To Rainspell Island has a message of "Hey, it'll be alright." and it makes me cry with happiness. Rollerball made me cry with triumph.
• There is probably no-one called Em-a (pronounced Em-dash-a, "'cause the dash don't be silent.") or suchlike. However, it is a plausible urban legend.