Derek put me onto this. It's a retro computer made from two Arduino devices, one of which generates VGA output. Many years ago I discovered that people were using PIC devices to produce video output, this does something similar with an Arduino to generate VGA video. It uses a tiny interpreted basic that is not a million miles away from my HullOS software, although the Basic implementation uses a lot more gotos....
Another moan that I have about internet marketing is the annoying habit of sending you unsolicited discount coupons, followed by a series of "urgent" messages telling you that the coupons are about to expire.
Well, really how daft do they think I am...
Most people don't really care about the speed that their programs run at. Unless they run too slow of course.
However, if really do want to know timings, C# provides a rather useful StopWatch class in the System.Diagnostics namespace that you can use to measure the time it takes your program to do something. You use it like this:
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
// Do something that takes a while
stopwatch.Stop();
Console.Error.WriteLine("It took: " + stopwatch.ElapsedMilliseconds);
It is especially useful if you're trying to re-write a program so that it uses parallel processing, and you want to find out how long things take to complete. Parallel programming is where your code makes use of all the processors in your computer, not just one of them. It should be faster.
I'm writing some stuff about parallel features in C# at the moment. For a book that I might have mentioned. So I wrote two versions of the code and then discovered, to my dismay, that the one I'd carefully optimised actually seemed to run slower than the original. I know that for small data sets a parallel solution might not be worth the effort of setting up all the parallel gubbins, and I also know that if there are any shared variables that the parallel code ends up fighting over, this can impact on speed, but whatever I did, the parallel version always took at least as long as the original. Wah. Took me a little while to find the mistake. Here's my code:
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
// Do single threaded version
stopwatch.Stop();
Console.Error.WriteLine("It took: " + stopwatch.ElapsedMilliseconds);
stopwatch.Start();
// Do parallel version
stopwatch.Stop();
Console.Error.WriteLine("It took: " + stopwatch.ElapsedMilliseconds);
The parallel version always, always takes longer than the serial version. Have you found the mistake yet?
Turns out that stopping and starting a stopwatch doesn't reset it. So the time for the parallel version is added onto the time for the original. And I'm an idiot. The method:
stopwatch.Restart();
- resets the stopwatch and starts it, so that my second operation is timed correctly. I'm now getting sensible speedups, which is nice...
Last year I wrote a book about Python. This year I'm doing another about C#. It's an exam text for the 70-483 Programming in C# Microsoft Certified Professional exam.
The Amazon site says, rather optimistically, that the book will be in the shops at the end of April this year. I'm fairly sure that it will be a little bit later than that.
But it will be well worth waiting for.
Twitter seems to be getting more and more desperate to get me to engage with it. In the good old days I'd get a message saying that someone had responded to something that I've posted. Now I get messages saying that someone I don't know very well and some else I don't know very well are now following someone I've never heard of.
If you fancy a nice night out, and you've already seen Paddington 2, then you should go and see Early Man. It's a fanciful tale involving prehistoric man, the bronze age, giant ducks and football. I really enjoyed it, and I'm looking forward to seeing it again - when I'm sure I'll discover lots of gags that I missed first time around.
We had a really good hardware meetup today at c4di. A whole bunch of new members turned up. along with a bunch of "regulars".
I did a talk about the latest developments on the Hull Pixelbot front. The system that controls the Hull Pixelbot has been renamed "HullOS" for marketing reasons, and is now available on GitHub. There's also a manual for the new scripting language supported by HullOS and an editor program you can use to create HullOS scripts and load them into the robot.
Finally, I've added the DXF files for laser cutting Hull Pixelbot chassis components, along with STL files for the 3D printed parts that you need as well.
I'll be adding more Hull Pixelbot stuff in blog posts over the next few weeks.
There were lots of really interesting conversations going on all round the room, which was great. We've still got room for more though, the next meetup is on the 15th of February. You can sign up here.
Brendan Dawes is the kind of person I want to be when I grow up. He goes around the world doing awesome things with technology and making stuff. His web page is worth a read, and he also has a newsletter that is well worth signing up for.
I'm not sure if Monzo is the "bank of the future". But I am sure that it provides a bunch of features that people are going to want in their future banks. Once you've used it for a while you start to think "Why can all banks be like this?".
Banks and their mobile phone apps have been getting steadily better over the years. We can now send money instantly and check our balances. But the balances always tend to lag between "real life" as payments and credits take their time to meander through the banking system. Monzo isn't like that. Within seconds of paying for something with my Monzo card my watch goes buzz and tells me how much I've spent.
The app keeps track of how much I've spent each day, and it knows the retailers I use, their location and the kinds of things they sell. So I can see how much I spend on coffee, petrol and groceries and do (or at least attempt to do) sensible budget type things.
The customer support is excellent and registering for an account was a snap (quite literally - as you have to record a 5 second video of yourself asking for an account as part of the process).
To add a bit of icing to the already nice cake, it turns out that you can use your Monzo card abroad without paying any of those nasty commissions that other card companies like add on top. It's actually based on Master Card technology, which means that it should work most everywhere.
At the moment you could't really call Monzo a "proper bank account". It's missing a few features that make it a bit hard to use as the only place you put your money. I'm using it by transferring lumps of cash from my main account into Monzo, and then using the Monzo card to spend it. This works very well though, the transactions go through very quickly, so tracking how much cash you left is very easy.
Monzo have big ambitions to challenge the high street banks, and they are adding features on a regular basis. What they're offering is a big step forward on what is currently offered by everyone else, I just hope they can find a business model that allows them to fund what they are delivering on a long term basis. Speaking personally, I'd be happy to pay a subscription to them just for the improved budgeting tools. I'm sure that all the other banks are looking very carefully at what Monzo are doing, and taking notes. Banking just got interesting.
You can sign up for a Monzo card here, although there is a bit of a waiting list. Existing account holders are occasionally sent "Golden Tickets" which they can pass on to their chums to get them on the system, so if you fancy having a go, just find someone with a bright pink card, and ask them for an invite.
They say that if you leave a gap in your blog posts for a while close to a full moon a magical post will appear mysteriously overnight.
I don't believe a word of it myself.
The them of the Global Gamejam was "transmission". Over in the university we had a bunch of teams exploring different aspects of this in lots of creative ways.
I had a bunch of Hull Pixelbots and a newly minted web editor that mostly worked.
Above you can see a nearly working display of Hull Pixelbots propagating a transmission from one to the other. Each robot is programmed via a web site using a scripting language that runs inside the robot.
The idea is that each robot "wakes up" the next one by moving close to it. The first attempt fails because the Mr White doesn't wake up Crystal Maisie,, and the second attempt shows my bad planning, in that it leaves Crystal Maisie in the way of the final move from The See Through Kid. Oh well.
Hopefully players of the completed game will be better at it than I was. I think it would be interesting for a large team, with each team member controlling a robot and a prize for the fastest transition from one end to the other, using all the robots at their assigned starting positions. I took some pictures during the judging, you can find all of the shots here.
Thanks to Simon and David from the university for organising such a great event.
Sorry the image above is a bit blurry. My lovely Fuji camera takes fantastic pictures, but only if you're patient enough to let it finish focusing before you take the shot.
Anyhoo, We had great fun at the Raspberry Pi Jam in the Central Library in Hull today. I've written before about how any carefully designed user interface never survives contact with the user. Same happened to day when I turned some kids lose writing little programs to control robots.
The good news is that making robots do what you tell them was sufficiently intriguing for folks to ride over issues with the interface, and everyone had great fun in the end. I left the event determined to get enough robots together to allow people to do some proper co-operative (or competitive) action. And set up something rather interesting.
Then it was on to the Global Gamejam event at the university. The theme of the competition is "Transmission". I've got a plan for that. Involving robots.
I think I must be feeling a bit better, because I've started making stupid mistakes again. Starting with telling off the database for refusing to find something that I knew was there. After all, I'd put the record there, hadn't I? Turns out that I had. Twice. So my request to find a single item with a particular name was failing because there were two of them.
After a bit of tidying up I've got something mostly presentable. I want to use it tomorrow at the Raspberry Pi Jam in Hull, and also as the basis of a Global GameJam entry.
Well, I've got the user interface just about built now, and most of it works - at least on a local machine. I'm starting to quite like writing ASP, which I'm told by some is a scary thing to say.
Not well today. Let's just say that there's a particular room in the house that I can't be too far away from just at the moment. And I've got a horrible sore throat. What better time to write code? After all, the day can't get any worse, can it?
For some time I've been meaning to write a web programming interface for the Hull Pixelbots. I want to use MVC Active Server Pages and host the project on Azure. And today I got started on the project. I've not done this kind of thing for a while, and it was a journey of discovery in many ways. There's a very good tutorial on how to do it here.
By the end of the day I've got the basics working, and I'm feeling a lot better. I think coding while ill works well for me.
We spent some time last night playing Fibbage. I first played it earlier in the year at David's. It's so good I actually bought a copy. It's a great party game. You need a PC, preferably with a big screen, and each player needs a device with web access. Then the game invites players to invent answers to silly questions and search for the correct one.
And no, I'm not saying it's good just because I won. Although I did. Perhaps those years of being a lecturer have turned me into someone good at inventing plausible lies....
Hull Devs is having another of their very popular developer events on the very last day of the month. On Wednesday 31st January at c4di in Hull you can hear talks dashboards and monitoring. These talks are really useful even (or perhaps especially) if you're a student. You can register here.
I've spent a chunk of today improving the Hull Pixelbot software. The improvements were identified when I was showing off the software at the hardware group last week. There's nothing like showing off your stuff to flag up faults and issues in it. Things that seemed like carefully thought out design decisions turn out the be horrible ways of doing things. And if you're lucky the person you're trying to impress will come up with ideas and suggestions that will make what you've building even better.
Perhaps you might be a bit afraid of doing this, but in my experience it makes a huge difference to the quality of a product to have someone take a look who hasn't spent ages living with it.
I remember when mp3 players first came out. They weren't cheap. Now they are 88 pence. Brian showed me one at the Hardware Group on Thursday.
Going to the group is always a calculated risk for me, in that people frequently show me things that I want to buy one of. Mind you, at 88 pence each I can afford to go mad and order a number, so I've bought 5.
They can be controlled by an Arduino (or any other device with digital I/O) or directly. You'll need a micro-sd card to hold the music and a speaker of some kind of course, but I'm thinking of using them to make an orchestra of Hull Pixelbots.....
There's been a lot of talk in the press about the Meltdown and Spectre vulnerabilities inherent in modern computer systems. For anyone out there who is concerned, I can confirm that there is no danger of any Hull Pixelbots being compromised by either of these issues.
Actually, to be serious for a moment, the important thing about these two clever pieces of nastiness is that they let a naughty program read another part of your computer memory. They don't directly allow a program to attack your system.
If you happen to be running a missile control password management database at the same time as browsing the murkier corners of the internet and running a cracked copy of Photoshop then you might have cause to worry, but most people don't do this. At least, I really hope they don't.
One of "Robert's Rules" is "A system complicated to be useful will have bugs in it". A corollary (posh word) is "A system complicated enough to be useful will be vulnerable to attack".
That's why we wash our hands before eating, have locks on our houses and make sure that our computer has the most up to date security patches.
Rob Miles is technology author and educator who spent many years as a lecturer in Computer Science at the University of Hull. He is also a Microsoft Developer Technologies MVP. He is into technology, teaching and photography. He is the author of the World Famous C# Yellow Book and almost as handsome as he thinks he is.
Begin to Code with JavaScript is now available for purchase and download. You can find it here
