August 3, 1977 was the public introduction of the TRS-80 home computer. Which is as I write this is more than 35 years ago. The most recent episode of this developers life ('Dinosaurs') brought back memories to this first real computer I could get my hands on. The setup as shown here is exactly what my father bought about thirty years ago. A black and white 12" monitor (16 lines of 64 characters), a 1.77 MHz processor and 16KB of RAM. Program storage on a cassette tape recorder which meant loading a decent game would often take 10 minutes or more. And to me it was magic. From the very first time I switched it on and saw the READY> prompt I was hooked. To programming. I remember it started with the sample from the owners manual. No, not the obligatory 'hello world' but a Celsius to Fahrenheit conversion program. And after completing all samples I did a very simple Space Shooter. Written all in Level 1 basic, using all ASCII characters, so you can probably imagine it did not exactly look like "Skyrim' or 'Modern Warfare'...
Then one day I bought the latest edition of 'computing today', mainly because of the cover. Today games actually look like that, but back then those images could only exist in your imagination.
And programming a real adventure game, with "goblins', 'wizards' and ''barbarians' sounded like an extraordinary challenge.
So I spent weeks typing the the listings and converting the code from the original Commodere PET basic until I had a real working game which eventually I hardly ever played. It showed me that for me the real fun was in the programming itself, which it has been ever since.
The program as I written it has been long lost. It was stored on a cassette which we probably gave away when we sold the TRS-80, and I did not have a printer then to make a hard-copy. But guess what: it's on the internet. It took some searching but finally I found an article by Paul Robson and this one by Tony Smith on reghardware.com .
Both more or less describe the same experience, and on the site of Frank Fraser there is even a full scan of the listings. Looking at the scans I suddenly realized that I probably still had a copy of the magazine somewhere and so I did. The scans shown here all come from my personal copy. Actually I thought my copy would be 'cleaner' than Franks scans. But memory tricked me and the weeks of intensive use also left their marks on the pages, as can be seen in the section where the different graphics are explained.
For a moment I considered trying to rewrite the program using a TRS-80 Emulator. Just to see if I could re-live the excitement of that time. Probably not. And after playing the BBC version (which is included in the zip-file that contains the scans) I found this type of game is still not my favourite.
Lets face it, the most enjoyable part of recovering an old computer magazine are reading the ads. Like this one on the rear. 'Fully expandable to 32K of user RAM' and a 'Full set of upper and lower-case characters'. What else would you ever need ?
C-Scope
About computer programming, operating systems, gaming, gadgets, electronics and life in general...
Sunday, January 15, 2012
Back to The Valley. (in 8-bit country)
Labels:
Programming,
retro,
TRS-80
Thursday, November 10, 2011
Holy Cow, I Wrote An App !
(Of course the title refers to Raymond Chens post about the only book he ever wrote..)
In 15 lines of code... And it's an unique one. And it does something that is probably useful to (a maximum of) 10 people in the whole world.
Last year I bought an Archos 7HT Android Tablet. It was one of the cheapest tablets then and this means it has limited capabilities. One of the limitations is that it does not have an option to switch to portrait mode. It has no tilt sensor and there is no special button or built-in option for it. So if you display a webpage it is always in landscape mode which is sometimes inconvenient. Like when I want to view the a popular site that shows when and where it will rain in the coming hours. As I live in a small country, it could fit in one screen IF displayed in portrait mode.
So I decided to look into the possibility to force the standard browser to start in portrait mode, which is (as far as I'm aware) not possible. Then I found a reference to the 'WebView' ("A View that displays web pages") component and guessed that this could be a way to solve the problem. And it is. I just created a standard Android application, followed the instructions on the WebView reference page to place the component on the main page, and forced the view to portrait using the appropriate function (that I found on StackOverflow).. That's all. Here is the code:
package CScope.Buienradar;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.webkit.WebView;
public class BuienRadarActivity extends Activity {
/** Called when the activity is first created. */
WebView mWebView;
Button myButton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mWebView = (WebView) findViewById(R.id.webview);
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.loadUrl("http://buienradar.mobi");
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
}
The blue lines are actually the only code written by me, all the rest was generated by the Eclipse 'New Project' wizard. And when you press Run or Build a complete installation package is created in the 'bin' folder of the project that can be copied to the device. Let's face it, this is almost too simple.... So that even left me time to create a fancy icon.

(And if you by coincidence are one of these 10 people: you can download it it from here: BuienRadar,apk)
In 15 lines of code... And it's an unique one. And it does something that is probably useful to (a maximum of) 10 people in the whole world.
Last year I bought an Archos 7HT Android Tablet. It was one of the cheapest tablets then and this means it has limited capabilities. One of the limitations is that it does not have an option to switch to portrait mode. It has no tilt sensor and there is no special button or built-in option for it. So if you display a webpage it is always in landscape mode which is sometimes inconvenient. Like when I want to view the a popular site that shows when and where it will rain in the coming hours. As I live in a small country, it could fit in one screen IF displayed in portrait mode.
So I decided to look into the possibility to force the standard browser to start in portrait mode, which is (as far as I'm aware) not possible. Then I found a reference to the 'WebView' ("A View that displays web pages") component and guessed that this could be a way to solve the problem. And it is. I just created a standard Android application, followed the instructions on the WebView reference page to place the component on the main page, and forced the view to portrait using the appropriate function (that I found on StackOverflow).. That's all. Here is the code:
package CScope.Buienradar;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.webkit.WebView;
public class BuienRadarActivity extends Activity {
/** Called when the activity is first created. */
WebView mWebView;
Button myButton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mWebView = (WebView) findViewById(R.id.webview);
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.loadUrl("http://buienradar.mobi");
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
}
The blue lines are actually the only code written by me, all the rest was generated by the Eclipse 'New Project' wizard. And when you press Run or Build a complete installation package is created in the 'bin' folder of the project that can be copied to the device. Let's face it, this is almost too simple.... So that even left me time to create a fancy icon.

(And if you by coincidence are one of these 10 people: you can download it it from here: BuienRadar,apk)
Labels:
Android,
Programming,
tablet
Tuesday, October 26, 2010
3-D Television or television for 2 ?
3D Television is hot. To talk about...
Despite getting the impression from magazines, exhibitions and showcases that 3-D is coming fast to all of us, I have not actually seen one in the shops. And certainly I do not know anybody who has one. And most reviews I hear or see all mention the fact that it is 'just not really there'. The 3-D images do not look 'real', and most televisions suffer from 'shading' or contrast problems. And the fact that everybody has to wear 'electric sunglasses' probably does not help either.
Anyway, technology will improve fast and we'll probably see some decent screens at a reasonable price level by the end of next year. What I have not seen yet is a different application that might be more interesting to a lot of people: dual view. 3-D televisions repetitively show two different images. And the 'shutter glasses' just cover one eye at the time in so each eye sees only a slightly different image, thus creating the 3-D effect. But what if you fed the TV with two completely different programs and have the shutters cover both eyes at the time ? This way your wife can watch episode19745 of 'As the World Turns' while you are watching tonight's major league football match !.
(Yeah, I know you would both have to wear a headset as well, but I suppose that could be integrated in the glasses.)
Despite getting the impression from magazines, exhibitions and showcases that 3-D is coming fast to all of us, I have not actually seen one in the shops. And certainly I do not know anybody who has one. And most reviews I hear or see all mention the fact that it is 'just not really there'. The 3-D images do not look 'real', and most televisions suffer from 'shading' or contrast problems. And the fact that everybody has to wear 'electric sunglasses' probably does not help either.
Anyway, technology will improve fast and we'll probably see some decent screens at a reasonable price level by the end of next year. What I have not seen yet is a different application that might be more interesting to a lot of people: dual view. 3-D televisions repetitively show two different images. And the 'shutter glasses' just cover one eye at the time in so each eye sees only a slightly different image, thus creating the 3-D effect. But what if you fed the TV with two completely different programs and have the shutters cover both eyes at the time ? This way your wife can watch episode19745 of 'As the World Turns' while you are watching tonight's major league football match !.
(Yeah, I know you would both have to wear a headset as well, but I suppose that could be integrated in the glasses.)
Monday, August 23, 2010
In Touch with the Tablet (or why I DO like the Archos 7 )
Two years ago I was one of the first to buy a 'small form factor computer', the EeePc 4G. Almost hard to believe nowadays with the omnipresent Netbook, it was the ultimate gadget at that time. The idea that you could have a fully functional PC with a solid state disk, a 7" screen and keyboard for only €250,- was just too exciting. However I've been struggling with the so-called 'use-case' ever since. To be honest, the keyboard is just too small and too flaky for decent typing, the screen is too small for real work and even playing YouTube videos is almost too much for it's little processor.
Today the Tablet PC is what the Netbook was then. Tablets in all shapes and sizes are already released faster than you can read their reviews and the expectation is that the real flood will start in second half of 2010. Combined with the explosion of smartphones, touch based UI's are suddenly everywhere.
Of course there is no doubt that the iPad is the ultimate touch tablet. But I have this aversion towards computers that you cannot program yourself.And I don't like paying €100,- bonus just for the name, so there is a chance I will never own one. So along comes the cheap Archos 7 Home tablet. An Android based 7" touch tablet with 2 Gig internal memory and about 10000 times the processing power required to send a rocket to the moon.. All that for just €150,-! Actually there are a bunch of (even cheaper) Chinese tablets on the market like the iRobot / aPad, but they look cheap even on the promo-movies and most reviewers admit they are probably a bit too cheap. And of course there are 100 different tablets 'to be released soon/next quarter/beginning next year'...At least Archos is a well known French company with a solid reputation for building good media players and their model is available now !.So I guessed it could never be that bad and at least you get what is specified.
And I'm not disappointed.
First: it looks great. It has got a solid 'brushed aluminium'-look on the base and a nice black edge. The formfactor is really good. It's really comfortable to hold with both hands while scrolling with your thumbs.
The screen is pretty good too. At 800x480 resolution is just big enough to comfortably view websites without much scrolling. The colours are bright, the image is crisp and the brightness is good enough even when it's used outside (provided it is not too sunny). And the resistive touchscreen is.. ehm.. well...OK. This touchscreen is the usually the core of all negative reviews of the '7'. But I'm used to my Palm Vx, iPaq PDA and Garmin NĂ¼vi GPS so resistive touchscreens come natural to me. It's what you're used to. And I'm sure if the iPhone was your first touch experience you'll be disappointed with the Archos.
But I am not.
Although I'm not really sure whether it is the 'touch tablet experience' itself or the device I like. I've been using it for a few weeks now and I find myself regularly checking e-mail, reading websites, e-books and even comics. When fully charged it can be on standby for two days so I can just pick it up, touch it and check the latest news, local weather or just read some Dilbert strips. And I can even program it ! Using the Android scripting layer you can write Ruby, Perl or Python scripts, right on the device. Not that I will probably ever use it to write any productive code but it's just the idea that you can do it makes me feel at ease.
Anyway, if you're looking for a reasonably priced 'first try' tablet and you're not spoiled already by any Apple product it's worth checking out.
UPDATE(27/10/2010): Much to my surprise Archos recently released a firmware upgrade for the 7 HT . And somehow they managed to really improve the touchscreen response so it is actually pretty good now !
Today the Tablet PC is what the Netbook was then. Tablets in all shapes and sizes are already released faster than you can read their reviews and the expectation is that the real flood will start in second half of 2010. Combined with the explosion of smartphones, touch based UI's are suddenly everywhere.
Of course there is no doubt that the iPad is the ultimate touch tablet. But I have this aversion towards computers that you cannot program yourself.And I don't like paying €100,- bonus just for the name, so there is a chance I will never own one. So along comes the cheap Archos 7 Home tablet. An Android based 7" touch tablet with 2 Gig internal memory and about 10000 times the processing power required to send a rocket to the moon.. All that for just €150,-! Actually there are a bunch of (even cheaper) Chinese tablets on the market like the iRobot / aPad, but they look cheap even on the promo-movies and most reviewers admit they are probably a bit too cheap. And of course there are 100 different tablets 'to be released soon/next quarter/beginning next year'...At least Archos is a well known French company with a solid reputation for building good media players and their model is available now !.So I guessed it could never be that bad and at least you get what is specified.
And I'm not disappointed.
First: it looks great. It has got a solid 'brushed aluminium'-look on the base and a nice black edge. The formfactor is really good. It's really comfortable to hold with both hands while scrolling with your thumbs.
![]() |
| iPaq 3800 - Palm Vx - Back to the future of touch... |
But I am not.
Although I'm not really sure whether it is the 'touch tablet experience' itself or the device I like. I've been using it for a few weeks now and I find myself regularly checking e-mail, reading websites, e-books and even comics. When fully charged it can be on standby for two days so I can just pick it up, touch it and check the latest news, local weather or just read some Dilbert strips. And I can even program it ! Using the Android scripting layer you can write Ruby, Perl or Python scripts, right on the device. Not that I will probably ever use it to write any productive code but it's just the idea that you can do it makes me feel at ease.
Anyway, if you're looking for a reasonably priced 'first try' tablet and you're not spoiled already by any Apple product it's worth checking out.
UPDATE(27/10/2010): Much to my surprise Archos recently released a firmware upgrade for the 7 HT . And somehow they managed to really improve the touchscreen response so it is actually pretty good now !
Wednesday, May 26, 2010
Too late for Windows Phone 7
Things change. Some things change fast. Computer industry changes faster and mobile phone trends change at light-speed or beyond.
Just a few months ago I was excited to learn about the the upcoming Windows Phone 7. The demo's are awesome and it really looks like
Microsoft is serious about building a real phone OS. They actually gave up on backwards compatibility with the Windows Mobile OS (codename Dinosaur..) and chose a combination of the Silverlight and XNA. Technologies that are both targeted at rich content and game development. And they are giving the development tools away for free. Anyone can start building apps using the free Visual Studio Express . All very exciting.
But..
The first Phone 7 devices will not hit the market before September 2010..
And that is much too late. Googles Android has just hit release 2.2, making it an almo
st mature phone OS, and they will probably have release 3 by the time the first Windows phones are released. Development tools for Android are also for free, and maybe not as slick as Visual studio, Eclipse with the Android SDK comes pretty near. And it definitely beats the almost arcane development experience for the iPhone. But what is most important: the phones are already there. Some of the coolest phones of this moment (like the HTC Legend or Samsung Galaxy) run Android, and it is rumoured that the sales of Android based phones has just recently surpassed those of the iPhone. Which again makes clear how fast things are moving in mobile land. With the iPhone, Blackberry and Android firmly established when Windows Phone 7 arrives I give Microsoft very little chance of succeeding.
And did I mention thinks change fast ? I just found that Paul Graham (who is supposed to know) mentioned in his essay of November last year:
The only credible contender [to the iPhone] is Android. But Android is an orphan; Google doesn't really care about it, not the way Apple cares about the iPhone.
I don't think that is true anymore...
Just a few months ago I was excited to learn about the the upcoming Windows Phone 7. The demo's are awesome and it really looks like
Microsoft is serious about building a real phone OS. They actually gave up on backwards compatibility with the Windows Mobile OS (codename Dinosaur..) and chose a combination of the Silverlight and XNA. Technologies that are both targeted at rich content and game development. And they are giving the development tools away for free. Anyone can start building apps using the free Visual Studio Express . All very exciting.But..
The first Phone 7 devices will not hit the market before September 2010..
And that is much too late. Googles Android has just hit release 2.2, making it an almo
st mature phone OS, and they will probably have release 3 by the time the first Windows phones are released. Development tools for Android are also for free, and maybe not as slick as Visual studio, Eclipse with the Android SDK comes pretty near. And it definitely beats the almost arcane development experience for the iPhone. But what is most important: the phones are already there. Some of the coolest phones of this moment (like the HTC Legend or Samsung Galaxy) run Android, and it is rumoured that the sales of Android based phones has just recently surpassed those of the iPhone. Which again makes clear how fast things are moving in mobile land. With the iPhone, Blackberry and Android firmly established when Windows Phone 7 arrives I give Microsoft very little chance of succeeding.And did I mention thinks change fast ? I just found that Paul Graham (who is supposed to know) mentioned in his essay of November last year:
The only credible contender [to the iPhone] is Android. But Android is an orphan; Google doesn't really care about it, not the way Apple cares about the iPhone.
I don't think that is true anymore...
Labels:
Android,
Phone 7,
WIndows Mobile
Monday, November 09, 2009
Google link soup: Back to WEB 0.1
Only recently I took a look at the Google reader / My Stuff page which is part of the iGoogle portal. And boy, is this a mess... (Screen-shot on the right->)Fifteen Underlined links, one that is an image (the 'Google Reader' image and one in small print light blue at the bottom left.)
Seven buttons in two different heights, all different widths, one with an icon, one greyed and one button that is actually a dropdown box and a search box. Eight clickable menu items of which two have an icon in front of the text, two have it after the text, three have no icon and one is printed bold.And still they did not have enough ways to leave this page so there is a 'More' menu of which the last entry is the option 'Even More..'
Google apps on the web is a horrible UI nightmare. I really don't understand how they ever expect to take over the desktop from a browser centric OS if they continue on this path. Let's face it: it is already extremely hard to create serious office applications that run in the browser and meet even the minimum level of usability. I even dare to say it is impossible using the current state of the browser technology. I currently use a browser app myself on a daily basis and even though it's very well thought out, does everything we need and has a slick user interface, it makes me itch every time I use it. Every day I try at least ten times to move, copy or delete a file by clicking my right mouse button. Which brings up the browser context menu...
And when I move through the explorer-like files list it annoys me that every step through the tree just takes anything between two and ten seconds. So why did we spend the last decade in doubling computer performance every year to get faster interaction if we are now giving this all away because everything must run in the browser ?
Wednesday, September 23, 2009
Name your Number : Great Joy !

Recently I stumbled on site named WikiDump that loosely archives interesting but deleted items from Wikipedia. There I found an an entry on the 'Zuckerman number' that intrigued me.
And here is the Wikipedia entry that discusses the deletion.
What I considered strange about this is that the definition of this 'special numbers' seems quite valid. Although the usefulness of this (other than making it a programming exercise) seems arbitrary, I see no reason why mr. Zuckerman does not deserve his small area of fame for discovering it. So I decided to dig deeper...
The definition can also be found on PlanetMath, which claims to reference 'J. J. Tattersall, Elementary number theory in nine chapters, p. 86. Cambridge: Cambridge University Press (2005)'
Now this book is by no means a fake or in any way humorous collection of real mathematics. I briefly went over it and checked some facts and biographies, and it all seems pretty legit. The tricky part is that on 'Google Books' the referenced page 86 is not present. Mr Zuckerman himself though is present on several other pages, proving that he is in fact a significant mathematician. In fact he was co-author of 'An Introduction to the Theory of Numbers' (By Niven, Zuckerman and Montgomery) which is a book that is often referred to in math studies.
But when we search for the other author, Ivan Niven, we find that there is actually something called a 'Nivenmorphic' number. And the definition for this is ' an integer that is divisible by the sum of its digits when written in that base'. Which by now sounds familiar. To add a little confusion though, the official name for this seems to be a 'Harshad number'. And Harshad means 'great joy' in Sanskrit. So who said mathematics was no fun...?
Labels:
mathematics
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