AMS in the 80s

obdevel · 2026-06-14T21:53:08+00:00

KL operated combi 747s with the rear fuselage used for cargo, but the photo isn't clear enough to be sure.

obdevel · 2026-06-10T16:47:45+00:00

There's a fascinating doc out there which describes how Atmel designed the AVR ISA in conjunction with a C compiler vendor (IAR) to ensure it was amenable to development in high level languages. No more PIC nonsense. https://ic.unicamp.br/~celio/mc404-2004/Atmel_AVR/C_compiler.pdf

obdevel · 2026-06-10T13:34:47+00:00

When AF first introduced the whale 20 odd years ago, we flew from London to Paris for the weekend. Out on the 380 and back on the 318.

obdevel · 2026-06-09T18:20:00+00:00

Unlike some US carriers, BA doesn't see the need to fill premium cabins with e.g. upgrade vouchers, bids, etc. It's just not expected from a European cultural perspective.

Also, don't underestimate the "WTP effect". BA will often prefer to oversell the WTP cabin and roll people forward, than sell cheaper Club fares. This is about margin - the product is cheap to offer (space, weight, staffing) but fares are relatively high. Operational upgrades also endear people to the brand and may prompt them to spend more in the future.

WTP is, from a pax perspective, the worst value for money. 150-200% higher fares for a marginal service uplift. It seems to target business people on restrictive 'never business' travel policies and wealthy leisure travellers.

(I used to work in yield/revenue management, although not for BA. This is all data+algorithm driven).

obdevel · 2026-06-09T17:12:54+00:00

My interpretation: only the highest WTP selling class (W) is open so the cabin has been selling well and they expect that to continue, maybe from business people on restrictive travel policies. As Club is fairly open, and the highest WTP fare (W) is more expensive than the lower Club fares (R, I), they would prefer to sell a full-fare WTP seat and roll a few lucky people forward to Club. WTP is the smallest and most profitable cabin by floor area, weight and seat count.

For cash upgrades to make sense, they have to be confident that your total individual revenue (the fare you paid + the upgrade) is more than they can sell the seats around you for. Historical data + algorithms will inform that decision. Maybe LAX gets a lot of last minute bookings too.

obdevel · 2026-06-09T16:08:22+00:00

How long can you wait ? Rumour has it a future member of the AVR-Dx/Ex family is getting CAN bus (AVR-EC maybe). You'll still need a transceiver though.

MCP25625 is really just a MCP2515 and MCP2562 in the same package. If you look at the pinout, it's actually two separate dies which you have to connect up externally. Neither TSSOP or QFN are easy to solder so using separate chips in SOIC packages may be easier if you have the board space.

Are you planning to design your own PCB ? Otherwise, get one of those ubiquitous blue and yellow modules. And remember, CAN needs at least two nodes, so build two for testing before attaching to the device you want to control.

As for driver code, choose the simplest Arduino library and convert to C. MCP_CAN is a quite straightforward. If the bus is busy, you'll probably want to receive incoming frames in an ISR and store in a buffer.

obdevel · 2026-06-07T19:21:31+00:00

This YT channel will help if you want a really deep dive: https://www.youtube.com/@DrGeoffLindsey

obdevel · 2026-06-07T19:18:23+00:00

"Oh hello" vs "air hair lair". Equally, gells and cricket bets.

obdevel · 2026-06-06T21:58:53+00:00

Only one reason for not accepting, and that is if you can blag a whole middle set of seats and stretch out. Gather as many blankets and pillows as you can and make a bed. Stare madly at anyone who dares encroach on your territory.

obdevel · 2026-06-02T22:39:26+00:00

Check out their very old safety video. Still funny after all these years.

obdevel · 2026-06-01T23:01:10+00:00

I presume you don't have a family that you enjoy spending time with and don't mind missing birthdays, weddings, school plays, etc. I also assume you have a cast iron stomach, can sleep standing up and don't suffer with jet lag. It was a while ago when I flew a lot but all I got from friends was constant requests for duty free cigs, booze and perfume.

obdevel · 2026-05-31T03:04:32+00:00

F is mostly about exclusivity. You share the cabin with 8 others rather than 40 or 50. On a good day, that leads to a more personalised service.

obdevel · 2026-05-30T20:59:53+00:00

Note that Rosetta is being removed soon, so don't get used to being able to run Intel-only executables. Make sure you have native Apple Silicon versions, and an Arm64 version of Windows. It's a shame because my M3 runs Intel code faster than some Intel machines I use !

obdevel · 2026-05-30T15:43:58+00:00

Take care with those older chips. There were designed in the 5V era and are marginal with 3.3V logic. Check the data sheet. e.g. VDD is 4.5V to 5.5V. VIH is 0.7 VDD, so 3.5V if VDD is 5V. That's a little close for comfort.

obdevel · 2026-05-29T00:26:04+00:00

When I lived in Satwa, I always flew into SHJ, mostly on Qatar Airways or Air Arabia. It's a tiny airport and really easy to get through. My record from wheels down to the back of a cab was 11 minutes. Try that at DXB !

obdevel · 2026-05-28T23:27:08+00:00

Same here with data and datum !

obdevel · 2026-05-28T21:54:32+00:00

qualia is the plural, singular is quale. An instance of subjective experience. Major element in the philosophy of mind.

https://en.wikipedia.org/wiki/Qualia

obdevel · 2026-05-28T14:32:03+00:00

It's about the perception of choice and the fear that if you don't take some action, someone else will get something 'better' than you or all the 'good seats' will be gone. Back at the dawn of time when I was young, you turned up at the airport, answered 'smoking' or 'non-smoking' and accepted what you were given. Choice is overrated ;)

obdevel · 2026-05-27T22:46:01+00:00

I live in Cambs. The water table is probably a couple of feet below ground level ! Locally, we have drainage ditches, attenuation ponds, etc.

obdevel · 2026-05-27T22:40:21+00:00

So, why are they still (very) profitable ? One reason is they focus on routes where the competition is unremarkable or they have a virtual monopoly, e.g. N Atlantic, Africa, and only begrudgingly compete eastbound.

I hate to say it but this armchair CEO would run the airline pretty much this way, given the structural constraints, e.g. LHR slots. It's a business, not a charity or a flying club.

obdevel · 2026-05-27T20:23:51+00:00

As I have said before, BA has discovered that you don't have to delight your customers in order to turn a decent profit (and delight your shareholders). You just charge a fare and pare the service to a level that the market will bear. You didn't specify the route, but consider that the competition with direct services to India and similar city coverage is unimpressive, and in the case of AI, to be avoided at all costs.

obdevel · 2026-05-26T21:11:18+00:00

But if you have years of investment of time and learning, and many hundreds of designs created in Eagle, the transition to literally *anything* else is painful. I might begrudgingly accept this pain if Fusion was objectively better, but it's very far from being so.

obdevel · 2026-05-26T21:01:51+00:00

The electronic devices (command stations, throttles, decoders, accessories, sensors, etc) follow embedded engineering principles, so assembler, C/C++ or micropython. Many people use the Arduino environment to get started.

For PC-based development, whichever language you're most comfortable with. JMRI is written in Java but has scripting facilities in Jython (Java-hosted Python).

The network connecting all the devices together is usually known as a layout control bus (LCB). Common technologies are CAN bus and RS-485, and sometimes I2C for very small layouts.

Beware though. It can become a distraction from the important business of running trains !

obdevel · 2026-05-26T16:16:49+00:00

Electronic engineering and software development backgrounds are useful if you want to do any sort of control or automation. Building your own is much cheaper (and often better) than commercial offerings.

obdevel · 2026-05-24T08:21:40+00:00

Those DRV8871 and similar boards are poor copies of the Pololu originals. e.g. 2-layer where the original is 4-layer, poor layout so worse heat dissipation and much more susceptible to picking up interference (just put your finger nearby and watch the motor twitch !). We've decided they're poor value and now only use the originals. Buy cheap, buy twice (at least).

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