Posts by Robert Lougher 11 publicly visible posts • joined 3 Sep 2007
Marconi and HMV (His Masters Voice) were both brand names of EMI. At that time they had a large consumer electronics business. They also conducted large scale R&D, with the worlds first complete television system, stereo sound recording, radar, computers and the CAT scanner. All of which has long gone. As with much of our "industry", EMI is a shadow of its former self.
The information is somewhat garbled. Fellow enthusiasts and I have been discussing the telly for a while:
http://www.vintage-radio.net/forum/showthread.php?t=65666
The television was sold some 3 weeks after the start of the BBC television service. Initially this was broadcast using the Marconi-EMI 405 line system (interlaced) and the Baird 240 line system (non-interlaced). The systems operated on alternate weeks. Televisions sold at this time had to support both systems, and they had a 405/240 line selector switch.
The Baird 240 line system was dropped at the start of 1937. First generation televisions sold after this date do not contain the extra valve and switch needed for 240 lines and have blanking plates fitted instead.
The problem is, many sets were returned to the factory for servicing, and any sets with the switch and 240 line circuitry had it removed. So now we have sets which never had the switch, and ones which had it removed. It is hard to tell exactly, as they both have blanking plates fitted.
Because this set was sold before 1937 we can say it definately will have had the circuitry and the switch. However, like all sets it had it removed and a blanking plate fitted. The switch is not original (it is completely wrong) and it is not connected to anything.
Having said that, it is still an interesting set. Some extra notes:
1) The television service was broadcast from Alexandra Palace, not Crystal Palace. It closed down for the duration of WWII, but reopened in 1946.
2) These tellies use the Marconi-EMI 405 line system, that was finally turned off in 1985 (although 625 lines had been in use since 1964, and PAL Colour since 1967).
3) Using a standards converter converting from 625 to 405, you can connect up pretty much anything you want to it. I've even demonstrated playing a PS3 on mine.
I've had a Toshiba AC100 for 10 days, and I'm very pleased with it. The difference is that I wiped Android off of it as soon as I got it and replaced it with Linux (Ubuntu 10.10). I don't know so much about the Folio, but definately for the AC100 Android is totally unsuitable. Linux, however, works OK*, and it makes a nice little portable development system. So it's a case of nice hardware, shame about the software.
* Information on installing Ubuntu can be found at the link below (although I did not follow them exactly). Currently, sound is not working.
http://tosh-ac100.wetpaint.com/page/Ubuntu
I've been part of the GNU Classpath community for many, many years (I write JamVM) so I'm well aware of the GNU Classpath exception that Sun adopted when releasing OpenJDK.
I agree, distributing a source file derived from a decompiled class file complicates things. However, you are being extremely disingenuous quoting the Classpath exception. The intention of the exception is to enable software to be used with OpenJDK/GNU Classpath without it becoming subject to the GPL itself (in a similar way to the LGPL).
"As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent modules,
and to copy and distribute the resulting executable under terms of your
choice, provided that you also meet, for each linked independent module,
the terms and conditions of the license of that module. An independent
module is a module which is not derived from or based on this library. If
you modify this library, you may extend this exception to your version of
the library, but you are not obligated to do so. If you do not wish to do
so, delete this exception statement from your version."
In no way is the decompiled class file an executable, and in no way is decompiling linking to produce an executable.
Ah, in what way have they fulfilled the GPL? They put an Apache license on a GPL'ed file. They can't do that. Just because code is open-source doesn't mean you can rip it off and do what you like with it. Do you know anything about the GPL or open-source software?
And they doctored the source because the file in Android has been derived from decompiling the class file. Hence the anonymous arguments (e.g. flag, etc.), lack of generics (Java uses type erasure, generics stuff is not in the classfile), and the difference in for/while loops.
As has been pointed out umpteen times, the Android file is obviously the result of decompiling the Sun class :
- The class file contains the names of member variables but not locals. Hence the names and ordering of the private variables are the same, but the method arguments have been changed to "boolean flag", etc.
- Java implements generics via type erasure. The type arguments are removed by the compiler and are not stored in the class file. Which is again why the generics inforation is missing from the Android version.
- for/while loops, etc. are translated into compares and branches in the class file. A decompiler doesn't know what they were originally, and will convert them all to the same generic while loop.
- References to constants are replaced by the constants themselves when compiling. Hence the use of hard-coded constants in the Android version.
To somebody who knows the class file format, the two files are identical in every way.
Actually for your information it *is* hard for Oracle to port Java to Mac OS X.
1) AWT implementation on Windows uses Windows graphics calls
2) AWT implementation on Solaris/Linux uses X-Windows calls
Apple's version of Java used OS X graphics, and according to Gosling, several secret APIs.
So unless you want to run your Java apps on Mac OS X using X-Windows, a port is much more than just a quick recompile. Sun had to do a version for Solaris. The Linux version shares much of this code. So, unless Apple donates their code to Oracle, I can't see Oracle bothering to do a Mac version anytime soon. As you rightly said, they're in different sectors. I doubt they could give an unshat fig about Apple. Apple tried it on with IBM over the PPC and lost.
And I'm using Java here deliberately. A port of Java is more than just the JVM. The graphics, etc. are part of the class library implementation, and is not part of the JVM proper.
The Java implementation is a port of JamVM/GNU Classpath. It was first ported back in November last year :
http://gnu.wildebeest.org/diary/2007/11/22/free-your-iphone/
Of course, it isn't "Java" as neither JamVM or GNU Classpath has passed Sun's TCK. But as Sun doesn't make this available to open-source projects it's hardly surprising.
Yes, Sun has announced a new licence for the TCK, but this applies only to implementations substantially derived from Sun's OpenJDK, which neither JamVM or GNU Classpath is.
OpenJDK Community TCK license:
http://www.infoq.com/news/2007/08/openjdk-jck
"UNIX has been playing catch-up with Windows NT since 1990, and it still is not as powerful. Buy Visual Studio, get a copy of Hart's book on system programming, and actually learn something about computers and programming."
I see somebody who actually believes Microsoft's propoganda. Where is your evidence? OK, what about the book you mention. Is it this one?
Windows System Programming (The Addison-Wesley Microsoft Technology Series) by Johnson M. Hart (Author)
I won't learn about computers from that. I'll learn about Windows.
This is exactly what the OOXML and ISO debate is all about. Microsoft and their supporters pushing closed and proprietary technology, versus those who care about openness, and making the best technology/standards for everbody.
The fact that users don't care doesn't make it right.
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