My RingGo Ordeal (by alaric)

Many months ago, I happened to park my red van in a car park in Swindon, that had a facility to pay by card over the phone. Which was great, because I didn't have enough cash for the ticket. All was well.

But then today, I parked my new orange van in a car park in Stroud, that has the same facility provided by the same operator. So when I ring the number, it recognises me, and says "To park your red Ford Transit, registration censored, in location some number, please press 1; to park elsewhere, press 2".

So I press 2. And it asks me the number of my location (a number printed on the sign). And it asks me for payment details. Then it says "Thanks! You now have a parking ticket! If you want to contact us, check out our web site on www.myringgo.com!" And hangs up.

I note that it hasn't asked me my vehicle registration; in other words, it's assumed I'm still in the same vehicle since I rang from the same number, and gave me no option to do otherwise. It didn't even actually confirm what I was paying for; it said what the parking would cost, but otherwise just asked me questions, and never said "Ok, are you sure you want to pay amount on this card to park registration in location for three days?" - so I continued through the process, expecting to be asked if it was the same vehicle or if I had a new one, and then suddenly found myself hung up and having paid to park the wrong van.

Anyway, my train is then arriving, so I jump on it, open my laptop, and connect to the wonders of the Mobile Internet: 25% packet loss and an average ping round trip time of 15,000ms (yes, fifteen seconds) but sometimes 80,000ms (yes, a minute and twenty seconds). I go to said URL, and it's reasonably usable; but once I've had my PIN sent to my mobile and logged in, it switches to SSL.

SSL, it seems, is highly latency sensitive, since it then proceeds to take five to ten minutes to load each page, as I excruciatingly navigate their menus. I find a list of vehicles, and lo, there's my red van listed - and marked as "locked" since it's currently got an active parking session, so it can't be edited. But it suggests that you can use the Contact Us form to ask them to edit a locked vehicle for you. There's no number to ring apart from the number to talk to the automated booking system that assumes I'm still in a red van; so I go to the form, and have to jump through all the hoops of the automated systems that try and stop people from actually talking to a human, confirming I've read the FAQs and all that (thankfully, the FAQs are on plain HTTP, so quite usable), and of course having to choose my type of query from a list (where most of the options try and direct you to a FAQ or another part of the site).

There's an option for Incorrect Vehicle! So I go for that. And lo, it takes me to the page to edit my vehicles, telling me I can't edit my red van because it's currently parked. So I had to go back through the system to try and find a generic problem type that will get me to a human, then submit a query. I submit the form, and it says they'll get back to me.

If they've clamped or towed my van when I get back, or try and fine me, I'll be ANGRY...

UPDATES: See the comments for the ONGOING STORY!

FORTH (by alaric)

Recently there's been some excitement in some corners of the programming languages community over the fact that Forth Dimensions has been scanned in and OCRed and is now available.

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Assertions (by alaric)

Assertions are a useful tool in defensive programming. If you're writing a bit of code that assumes some condition to be true, since that condition being true is a design constraint of your system so it can only possibly be untrue if there is a bug elsewhere in your code, then it can help to put an explicit assert of that condition before your code.

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First Class (by alaric)

Once a week, I go to London for a few days, almost always by train. It costs £42 if I buy a ticket from the station on the day - or, if I book in advance at TheTrainLine, as little as £16. Tickets ordered in advance are cheaper, but it seems there is a limited allocation of each price grade - as the more popular routes quickly sell out of £8 each way tickets, then the next level up (£11.50), then the next level up (£18).

However, when I booked the tickets for last week, for the return journey on Saturday, only the £18 ones remained - but, unusually, there were still some £19.50 first class tickets left.

I'd never travelled first class before. So, I decided I'd give it a try. £1.50 isn't much to spend on an experiment.

And my conclusion is: first class equals a comfier seat and the offer of a free biscuit and tea or coffee.

Which, if I drank hot drinks, would definitely be worth the extra one fifty, at the going rate for such things.

As a non-hot-drinker, I think I about broke even with my experiment, but on a journey of more than an hour, the better seat would be well worth a similarly small price increase.

But travelling first class is nowhere near worth the more than doubling in price (£116 rather than £42) it costs if you buy your ticket on the day. That's a total ripoff.

Bench PSU made from an old PC power supply (by alaric)

My first PC compatible was an actual PC. As in, the original IBM PC - not even an XT. It died a death, but I salvaged the power supply from it, with the nice red switch, to be a bench PSU for my electronics experiments:

It supplies -12v, -5v, 0v, +5v, and +12v. Which served me well for some years, but these days, everything's 3.3v or 1.8v. And my termination setups - first wiring directly into the row of screw terminals on a breadboard, then later a bit of wood with metal strips nailed to it so I could attach croc-clips easily - all left something to be desired.

So I got busy and built this:

Complete with a power LED so I can see at a glance if it's live:

Inside it's quite simple. Most of the terminals are fed directly from the PSU via the black cable, but I added an extra wire for an earth connection to the chassis (which I checked was really earthed) for ESD wrist straps. I mounted 3.3v and 1.8v linear regulators on a bit of stripboard along with the LED and its series resistor, and hooked it into the 0v and +5v lines.

Job done. Now the last bit of major infrastructure I need set up is to get Ethernet into the lab so the PC I have in there for driving the dev boards can access the Internet and my version control system...