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Halfway status report. Display - success

My computer is becoming wearable, though it's taking some time.

Half of the allocated time is gone already, and I feel like I should have accomplished a lot more. Also I feel like I'll be finished in a week, which is not true either. I now have a working computer, which doesn't yet seem to understand my 3g, working head mounted display, in monochrome as it's a lot more readable that way and I'm going to spend my time in command line anyway, and barebones keyboard, which has not yet been programmed because of missing atmega8 programmerthingy.

 My achievement this week has definitely been the display. I have bought a lot of cables and adapters. The Beagleboard gives S-video and Myvu Crystal wants S-video or composite, but it accepts a 4 conductor 3.5mm plug. Currently I have a modified S-video to RCA -> RCA to 3.5mm plug, but a while ago I had like four or five adapters and cables going around. That thing didn't "just work" and everything was a lot better after I had replaced the wiring. I did try to mess with the os settings for overlays, displays and framebuffers without enough knowledge, but the problem was with my cables. There was also the thing that first I didn't get any signal at all before Gregor Richards helped me a bit. There's just so much conflicting and old information, and not enough new information about s-video on Beagleboard+Ångstrom. I'll also have to thank a fellow student who has been helping me with some information and other things.

 I still need to modify them though. Myvu Crystal is a weird thing, as the usb-charging cable works as a ground, and so I shouldn't have another ground going to Beagleboard, because that messes the signal up. I already cut the ground pins there, but wasn't enough. Currently I get best signal if I leave those RCA cables hanging so that their grounds don't touch each other and I use the white RCA of the a/v jack and just touch the first metal thing on the Myvu pendant with the tip of the 3.5mm plug. If I use the red one and just stick the 3.5mm plug in, it gets worse signal. Probably because there's also sound signals going there. I need to break the plug so, that there is just the last tip that can connect to anything.

It's been irritating to look at micro sized flashing ntsc screen, but now it is perfectly readable and the signal is just perfect. After I've fixed the cables, I'll just need to break the myvu and put one of the displays inside some sunglasses I'll be buying soon. I'll also need that stupid half-silvered/see-through mirror which will be in front of my eye and which will allow me to see through the display. Then the display is done.

It could have been a lot easier and better, and still might be, if I'd just buy the correct driver chip from Kopin. It's "just" 50$ and the correct is that version where I could bypass the composite and just feed it a pure digital display (I've been told that myvu pendant has the driver board version that has some stupid chip which you can't see it's pins so no wiring there). That way I could have used the dvi-d signal of Beagleboard and everything would be lollipops and rainbows. They still are, but they would be the colored things that way. There are some nice specifications at Kopin webpage. For your information, Myvu Crystal uses Kopin 640x480 microdisplays. Driver board might, or might not be Kopin, but it has the same chips that handles the signals and probably the same decoder for composite/s-video signals. 

 I'll be getting the chip for the keyboard (Spiffchorder) soon, but I'll need to rewire the keys and craft a handle for it. I'll try making one from finfoam. Then the keyboard is also done, if it can type scandinavian letters like ö and such. If not, I might need to touch their code too.

My computer needs wvdial or something similar, so it could use my 3g. It also needs a box, maybe from finfoam. Maybe I should make the box from some clear plastic though. I have ordered a usb ethernet card just because I'll probably need it sometimes. I'll need to decipher why narcissus, the awesome Ångstrom distribution image builder gives me enlightenment and gnome-games and such, when I clearly order a command-line only setup. I don't know what I should kill to get to command-line now. Alt+ctrl+F1 doesn't work, though it clearly has worked sometimes for some unfathomable reason. If I just kill enlightenment, xorg and/or gpe-login, they will just restart. I should study my chosen distribution a bit more.

And finally, I'll need a battery. I'm thinking about those rechargable batteries, I've seen some high mah ones that should do with some kind of a 5V regulator.

 I'm trying to do most of the keyboard this weekend, then I'll check the software I'll be using and the cables. I need some new, short cables, It's been a joke of the day that I could use them as my only clothing. It also seems that being mobile doesn't mean not having lots of wires around. After my keyboard is finished, I'll build the computer case and the sunglasses-display, and afterwards, I'll make the battery and start wearing the thing when I'll manage to find a way to wear them. Maybe I could just hang the computer from my belt. I definitely don't want a fannypack or a backpack. Maybe something like the Casebelt from Urban tools. Do you know some nice way for wearing the wearable? Comments welcome.

 

–ø–µ—Ä–≤—ã–π –ø–æ—Å—Ç

–°–µ–≥–æ–¥–Ω—è —Ö–æ—Ç–µ–ª –æ–∂–∏–≤–∏—Ç—å —Å—Ç–∞—Ä–µ–Ω—å–∫–∏–π –∫–æ–º–ø –¥—Ä—É–≥–∞, –∫–∞–º–µ—à–µ–∫ —Ç–∞–º 3 –ø–µ–Ω—ë–∫ –∫–∞–∂–∏—Å—å 500mhz –ø–æ—Å—Ç–∞–≤–ª—é —Ç—É–¥–∞ –ª–∏–Ω—É–∫—Å –∏ —Å–¥–µ–ª–∞—é –≥–µ–π—Ç–∏–∫ –¥–ª—è –¥–æ–º–∞—à–Ω–µ–π —Å–µ—Ç–æ—á–∫–∏. –ù–æ —á—Ç–æ —Ç–æ –Ω–µ –ø–æ–ª—É—á–∏–ª–æ—Å—å. –í—Ä–µ–º—è –Ω–µ —Ö–≤–∞—Ç–∏–ª–æ. –ó–∞–π–º—É—Å—å –∑–∞–≤—Ç—Ä–∞.

 

Journey to Android programming (hell?) Heaven. Part II

Arrrrrrghhh.   I've got past having the basic environment installed.  I've said hello to the world with and without a picture on the screen.  I've run through a tutorial that has me putting little red dot's on a horrendously green background. I've not a clue what in the hell I've done. 

One of the hassles of OOP is that there is a lot of background magic that happens.  Most OOP programmers understand the basics of the incantations.  But can't explain it.   I understand why they can't, because frankly they don't think about how they do it.  They just do it.

It's a lot like walking, or even more so, learning to walk.  As kids we don't have the tools to think about how to walk.  We only have the desire to go upright like all of the other humans around us.  We do it but 'we never actually think about HOW we do it.'   People, whom as an adult, need to relearn walking are often hindered by their increased cranial capacity, as they often spend too much time thinking 'what was it I used to do' instead of just doing it.  

In many ways I'm in that same position.  I'm spending too much time worried about cause and effect of my actions, and too little time just doing it.  I'll admit, like any other Admin out there, I love poking things with sticks and rationalizing the results.  OOP doesn't always behave rationally.  Oh I'm sure that class and the methods it invokes where rationally created, at the time of creation, but for me,  it all still seems irrational, and will continue to be so until I learn how to think like a programmer.

Right now I'm cursing at Eclipse, and ADT.  If I launch the emulator manually with the -scale option I can scale the emulator really nice (fit's my little 4G monitor just fine.  However for the life of me I can't figure out where to put the necesary option into Eclipse 3.5 such so that it passes it to the emulator launch commad.  *sigh*.  You'll know I've got it right when I blog it as a how to for sure.  Until then, OOP's

 

 

 

Improving Putty settings on Windows

Improving Putty settings on Windows

If you are using windows machine to connect to Linux machine, putty is inevitable. Here are some of tips you can use to customize to have cool look, more efficient to work 

Configure your Putty first, then make entries.
This is important advice. First configure your environment before you start using it. This is especially true for Putty, since you always start of from the default, it is important to configure the default entry before you create entries from these defaults. It will save you a lot of time afterwards to get things straight.

So before you make any changes, open the default template in Category: Session by selecting Default Settings and pressing the Load button.

Make SSH the default.
If you have an older version of Putty, chances are that you have Telnet as the default protocol. Changing it to SSH will probably save you some time when you start Putty out-of-the-blue. For this go to Category: Session and select SSH.

Increase scrollback buffer.
By default Putty buffers 200 lines of output, which is too little in lots of circumstances. And the moment you actually need this number increased, chances are you already lost some information you wanted. So it is wise to increase this number. What I do is go to Category: Window and increase Lines of scrollback to 20000.

Choose a good font.
The newer Putty binaries are able to make use of ClearType which drastically improves the font quality compared to Antialiased. Go to Category: Window > Appearance, choose ClearType and a nice font. I prefer Lucida Console, 9-point.

When you are there, you might want to change the Gap between text and window edge to 3 pixels.

Use proper character encoding.
Nowadays all Linux systems are able to use Unicode (UTF-8) so to make sure that the output in Putty (especially everything non-ascii) looks fine, go to Category: Window > Translation and change the character set to UTF-8, make sure that also the line drawing characters use Unicode as well.

Linux copy-and-pasting.
I prefer to do an implicit copy when selecting and using the middle mouse button for pasting. So I go to Category: Window > Selection and set the Action of mouse buttons to xterm (Right extends, Middle pastes)

When you are there, also enable the option Paste to clipboard in RTF as well as plain text, which is nice when you are copy-and-pasting to emails or text documents that allow fonts and colours. Your console output will look much the same as it does on your screen!

Change dark colours on a black background.
One of the more annoying things with terminal applications (xterm has the same issue) is that by default dark-blue is too dark to be visible on a black background. Not only is this frustrating, it makes the experience for new users so bad that they prefer to disable colours (or hate the ls colour output or syntax highlighting in vim).

So if you are like me, go to Category: Window > Colours and select ANSI Blue in the Select a colour to adjust to Red:74 Green:74 Blue:255. I do the same for ANSI Blue Bold to Red:140 Green:140 Blue:255.

Keeping idle sessions active.
Another frustrating problem is induced by the time-to-live of inactive or idle TCP sessions on firewall or switch configurations. At some companies this is put aggressively low so that TCP sessions that have no activity for 1 minute or even 30 seconds are being dropped. If you are using an SSH connection over such a network device, you have to take care to send keep-alive packets over your idle session. To do this go to Category: Connection and set Seconds between keepalives (0 to turn off) to 25.

Finally, saving the default.
Now, don't forget to save the changes you just made to the default template. If you loaded the Default Settings at the start, return back to Category: Session and press the Save button. Now you are done !

Putty settings summary.
Category: Session
Connection type: SSH

Category: Window
Lines of scrollback: 20000

Category: Window > Appearance
Font: Lucida Console, 9-point
Font quality: ClearType
Gap between text and window edge: 3

Category: Window > Translation
Character set: UTF-8
Handling of line drawing characters: Unicode

Category: Window > Selection
Action of mouse buttons: xterm (Right extends, Middle pastes)
Paste to clipboard in RTF as well as plain text: enabled

Category: Window > Colours
ANSI Blue: Red:74 Green:74 Blue:255
ANSI Blue Bold: Red:140: Green:140 Blue:255

Category: Connection
Seconds between keepalives (0 to turn off): 25

 

 

Journey to Android programming (hell?) Heaven.

I've begun my journey.  May God have mercy on my enternal soul.  For whatever reason, I've broken down, and have begun the journey into programming, again.   Now I did this once before, the part about learning programming that is, and  I'm not sure I want to repeat my initial disaster.

 I began my programming career with Fortran IV (the Watt book,  also known as "What For")  back in the days of punch cards and paper tape.  When other schools had dumb terminals in rooms that undergrads could use, CWRU had the punch card. 

I dutifully created my little deck of cards, took it to the reader area, handed it to the proctor, and began my wait.  Do to scheduling with the main frames at Chi  Corp, lowly undergrad computer time was way delayed.  Two days later I dutifully reported back as requested and found out that my program that did x+y=z worked, and I had the green/white 80 column paper output to prove it, and I was underwhelmed. 

 Now I'm the kind of person who craves instant gratification.  I'd seen my fraternity brothers spending hours with red pens pooring over reams of the green/white afformentioned paper. I'd even helped in some of the debugging sessions. Did you know that on a Honeywell main frame +0 and -0 are the same thing but not equal?  I'd spent hours helping people re-order their cards for a major project when they accidentally dropped the box.  The feedback loop from programming didn't run fast enough for me.  I was soon off in a different direction.

A switch of schools and then career objectives got me into electronics and most importantly the management of long haul microwave communication systems.  I was freaking hooked.  I could see the results of an adjustment to a multiplexer, radio, or equalizer,  immediately.  Trunks came back online, because of adjustments or repairs I made.   Then I found out about BBS's and computers re-entered my life.  (Amiga helped)

Flash forward from the early 90's to the late aughts and I'm finding myself need to come back to my first endeavor with computers.   I've been working on computer systems/networks since I first found Linux (Alzza Linux, a clone of RH 4.2 back when I was in Korea), and I consider myself to be a pretty dang good Admin.  NOT a programmer. 

 The hard part about that last sentence is that most companies don't understand the real difference between a programmer and an Admin.  You can't be good at both.  I'm not.  I'm just good at one, but, if I want to continue finding jobs (and right now I do need that) I'm going to have to bend to the winds of change.

 So in order to start I've found 2 things.  1.  A startup that needs admin work done, with a CTO who will teach me Java programming (from theory too, not just cut and paste)  2. A venue where I have something I want to create.  (My G1 is a toy/tool I play with constantly.) Put the two together and I'm back at the wheel.  

Yes programming, or at least learning it is still lacking in the adrenaline feed I need, but I'm working hard on putting myself out there to 'get her done' and get on with it.  Wish me luck, I've got helloworld under my belt and I'm off and walking. 

 

Adventures Thru Linux #! 1

So here I am after around 5 years, a member of linux.com and I expect my experience to be a good one. At this momment i've tried several distros including gentoo, knoppix, ubuntu, xubuntu, slackware, puppy, fedora core, red hat, suse, mandriva, openbsd and a few others. I'm not sure why i've tried so many (maybe because my laptop is so old it's damn near fossilised) but I am installing yet another distro that I hope will be my last, atleast for a while.

Crunch Bang Linux 8.04.2 LTS is my new distro of choice. Based on Ubuntu (probably the most popular and (IMO) easiest distro to use) and with the extremely lightweight openbox WM it should be a great fit for my pentium III beast.

Here is to the start of a great future with linux and my ongoing adventures thru it. If anyone actually read this blog, my condolences to you, and i'll be back shortly with a progress report on my "adventures thru linux #!"

 

 

 

Preparing for a (short) month in China

I'll be flying out next week to China to visit my in-laws and have them meet our daughter. We'll be in the country, in QiDong Shi, Hunan.

And I'm taking a couple of USB sticks with me (1 and 8GB), loaded to boot Ubuntu Jaunty 64-bit and 32-bit.

I am planning to build a computer there for my wife parents. And of course I want it to run a Linux distribution (and my favourite one as well).

Now it will be very interesting to see how the new computer and OS will be accepted by first time Chinese user! I'm actually wondering if I should setup one one my stick to boot the new Netbook remix... that would probably have all the required user firendliness (and eye candy).

 Yeah, let's test this out on a VM this week end ^_^.

 

Greetings

Greetings to and from my Linux.com blog! I just signed up to linux.com, congratulate me please. I registered a million years ago and never actually maintained my profile then. However since linux.com has revamped it's appearance and linux is becoming even more mainstream (I stress the EVEN MORE) I'm inclined to keep up to date with the buzz.

 

Google Chrome - I just installed Chrome and my first impressions about it are that it is fast and impressive. (I installed it on my Mac Mini Intel running WinXP SP3) I'm wondering if it's also available for Linux? I love the integration of Google products.

 

I'm currently downloading the latest HP MIE distro which is the new and innovative OS HP has designed and is shipped with the HP MINI 1000. I however own a HP2133 and I plan on an installation soon as the download is complete. I will post back my progress here.

 

Ispravljanje krive Drine - LAMP i problem sa belinama

Prošle noƒái sam izgubio 4h na debagovanje i modifikaciju koda koji je bio ispravan, ali nije radio – a ja sam jedva provalio o ƒçemu se radi. Glavni krivac bio je Windows, a šta se desilo, kako sam otkrio o ƒçemu se radi i kako sam problem rešio, saznaƒáete vrlo brzo :) Naime, razrešenje ove misterije nije išlo gore pomenutim redosledom, pa upravo zato i reših da svoje iskustvo podelim sa ostatkom svet.

Pretprošle noƒái krenuh u realizaciju jednog mog mini WEB projekta. Kako su pitanju XHTML/CSS + PHP/MySQL tehnologije, krenuo sam sa radom u lokalu. Startovah LAMP pa se bacih na izradu baze i back panel-a. Zakljuƒçno sa sistemom za logovanje korisnika, privedoh rad kraju za taj dan (noƒá zapravo) pa sam sve do tada uraƒëeno okaƒçio na server. Probao sam skriptu i sve do tada implementirano je radilo bez ikakvih problema.

Onda prošle noƒái reših da malo sredim kod, formatiranje i komentare, pa sam sve ponovo svuk’o u lokal, sredio i vratio online. Jedina razlika bila je što sam ovog puta radio sa WAMP-om na mašini sa Windowsom. Ništa znaƒçajno nisam menjao što se koda tiƒçe, ali ipak reših da još jednom proverim da li je sve ok. Kad imam šta i da vidim: na svakom fajlu pucaju neke funkcije (2-3 uproseku). Od svega su se najviše bunile sesije (kreiranje i promena podataka). Tu je krenulo 4h pakla sa istra≈æivanjem šta taƒçno ne radi i zašto se od jednom buni, a prethodnog dana je radilo.

Probao sam sve i svašta. ƒåak sam i potpuno promenio sistem za logovanje. Menjao pamƒáenje nekih stvari u cookie umesto u sesiju i svašta drugo što mi je palo na pamet. No na kraju je ipak negde pucalo. Onda reših da sklonim komentare sa poƒçetka fajla, jer sam ƒçitao da neke PHP funkcije moraju biti apsolutno na poƒçetku koda (iako su u demo primerima, ƒçak i u dokumentaciji, radile i ako pre njih ima belina ili komentara). Iz web-editora sam otvorio, izmenio i saƒçuvao svaki fajl ponaosob, posle ƒçega je, na moje zaprepašƒáenje, sve ponovo proradilo bez ikakvih grešaka. U neverici sam ponovo vratio komentare, kako bih bio siguran da je do toga, no i dalje je sve radilo. Nekoliko minuta sam gledao u kod i ƒçeškao se po glavi dok se nisam setio sliƒçnih problema jednog prijatelja. Branku je pucao IE7 prilikom izvršavanja JavaScript-a pisanog na Windows platformi, pa sam pomislio da i ovde CR-LF pravi probleme.

Ovu teoriju sam eksperimentalno dokazao na sledeƒái naƒçin: Prvo sam sve fajlove upload-ovao preko FTP-a (text-modom) gde sistem autoamtski sreƒëuje EOL. Pokrenuo sam skriptu sa servera i nije bilo nikakvih grešaka. Zatim sam iste fajlove arhivirao i ponovo upload-ovao (ovaj put kao jednu arhivu, binarnim modom) pa otpakovao na serveru. Prilikom pokretanja skripte, ponovo su se javile misteriozne greške o nemoguƒánosti pokretanja sesija.

Suma sumarum: Ukoliko se bavite WEB development-om i radite pod Windows-om, imajte na umu da je veƒáina WEB servera pod nekim UNIX-olikim operativnim sistemom (Linux, BSD, Solaris, MacOS…) te da je preporuƒçljivo da svoje fajlove spakujete u odgovarajuƒái format kako ne bi dolazilo do ovakvih problema. Sa druge strane, ako radite u Linux okru≈æenju, a koristite komponente koje su razvijala treƒáa lica, obavezno proverite da li su sami fajlovi saƒçuvani na odgovarajuƒái naƒçin. Na taj naƒçin uštedeƒáete vreme i sebi i drugima ukoliko doƒëe do ovakvih problema.

* tekst orignalno objavljen na adresi:
http://www.plagosus.net/blog/programiranje/ispravljanje-krive-drine/

 

Exams come again

This my first article on linux.com

and the first thing i record is about exam,

and i hate exams, very much !!!

 

Linux.com lacking a "digg"-type button

I just thought that I would point this out and see what others have to say.  

The one thing that I keep finding when reading through linux.com is that I'll find an article that I find great and I want to indicate it as something I enjoyed by a "digg"-type button, but all I have is a "Favorite" button. 

That said, I realize that there is a real Digg button, but that would mark the article up in the ranks on the actual digg site.

 Request:  Add a button that I can use to mark an article as worth reading.  (I can mod up comments, but why not articles?) 

 
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