Wikipedia:Reference desk/Archives/Computing/2010 January 19

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January 19

Long Range wireless router

I need a wireless router that's longer range than most consumer type routers. I need to cover 3 floors of an older home...not super concerned with speed though. I can't run cables through the walls etc...it's been harder to find than I thought...ideas? 69.180.160.77 (talk) 05:25, 19 January 2010 (UTC)

Google wireless-g repeater. Comet Tuttle (talk) 05:38, 19 January 2010 (UTC)

It's not entirely a matter of range - three floors isn't much distance for a regular WiFi system. The bigger problem is the amount of intervening walls, floors and ceilings which attenuate the signal. Remember also that the signals have to go both ways - so while getting a higher power router helps in getting signals out to your PC's - it won't help with getting them back again because that's down to the transmitter power in the PC's - which you can't reasonably change. The idea of using wireless repeaters (as Comet Tuttle suggests) is therefore the better answer. SteveBaker (talk) 03:53, 20 January 2010 (UTC)

last logon time in yahoo mail

where do i find last logon date and time in yahoo mail —Preceding unsigned comment added by Ismail pcs (talk • contribs) 09:40, 19 January 2010 (UTC)

I came up empty after a couple of minutes' time in the help section, suggesting that Yahoo Mail does not have a feature letting you see this information. Comet Tuttle (talk) 17:37, 19 January 2010 (UTC)

I agree with you and as far as I know it's not possible to view the last logged in time on Yahoo (or Hotmail for that matter). It's probably not any help, but Gmail does offer this feature. ZX81 ^talk 17:54, 19 January 2010 (UTC)

I think Fastmail upon successful login automatically shows the time of last previous login attempt and whether it was successful or failed. - 23:35, 19 January 2010 (UTC) —Preceding unsigned comment added by 84.46.48.150 (talk)

Graphics in BASIC (1)

Resolved

I write graphics programs in BASIC using SCREEN 12 mode which gives a display size 640x480 pix and 16 colours. I would like to change the palette colours, for example to a 16-step grey scale, by POKE'ing bytes into the palette address. (There is a PALETTE command but I have not succeeded in using it to get what I want.) Can anyone tell me the address where the palette is stored? Cuddlyable3 (talk) 12:07, 19 January 2010 (UTC)

It is not stored in memory but in VGA registers, so you would need OUT instructions, or whatever they are called in Basic. (If not OUT try PORT or something.) —Preceding unsigned comment added by 195.35.160.133 (talk) 13:13, 19 January 2010 (UTC)

The part of the VGA you need to OUT to is called the DAC (Digital Analog Converter). It has 256 byte-triplets for the red-green-blue values of the max. 256 vga colors. Technical details here: [[1]]. Btw, PALETTE should work too, I think. 195.35.160.133 (talk) 13:25, 19 January 2010 (UTC) Martin.

In QBasic 1.1, when you are using SCREEN 12, you can use the PALETTE statement as follows:

PALETTE n, r + (256 * g) + (65536 * b)

where n is 0 to 15, and r, g, and b are 0 to 63. --Bavi H (talk) 01:11, 20 January 2010 (UTC)

PALETTE command in Turbo Basic is different. The second parameter is not an rgb triple, it is an index 0 to 64 into the VGA palette. (That's according to the manual. I wonder why 64 and not 63. On trying it I get various colours but no grey scale.) Cuddlyable3 (talk) 22:54, 22 January 2010 (UTC)

I couldn't find a manual, but did find a copy of Turbo Basic and played around with it. In QBasic, the PALETTE command accepts a different range of arguments depending on what SCREEN mode you are in. However, it seems the Turbo Basic PALETTE command only lets you choose from the 64 colors available in the VGA text mode (SCREEN 0 with a VGA monitor), no matter what SCREEN mode you are in.

value = (r and 1)*32 + (r>1)*-4 + (g and 1)*16 + (g>1)*-2 + (b and 1)*8 + (b>1)*-1

PALETTE n, value

Note: (x and 1) is 0 if x is even, otherwise 1. (x>1) is -1 if x>1, otherwise 0.

r, g, and b can be 0 to 3. value ends up being 0 to 63. (Not 0 to 64, probably a misprint in the manual.)

The only grayscale values are 0 (black), 56 (dark gray), 7 (light gray), and 63 (white). --Bavi H (talk) 07:41, 23 January 2010 (UTC)

The EGA color palette has more info about this set of 64 colors. --Bavi H (talk) 02:15, 24 January 2010 (UTC)

After a little searching, I found The VGA palette, QBasic, and you, which shows the appropriate OUT commands to use as a faster alternative to the PALETTE statement. --Bavi H (talk) 02:51, 20 January 2010 (UTC)

I found how to get the 16-step grey scale. The 16 colours numbered 0..15 mode have to be non-linearly mapped to palette indices thus:

for c=0 to 15   'c is colour
 select case c
   case 0 to 5, 7
     cc=c
   case 6
     cc=20
   case else 'i.e. c=8..15
     cc=c+48
 end select
 out &H3c8,cc 'put the palette index in the DAC Write Address register
 
 'write 3 bytes RGB of a grey tone
 for n=0 to 2
  out &H3C9,c*4  'DAC Data Register. Allowed values are 0..63
 next n
next c

ADDENDUM to archived answers: I suspect the above program works only for text-mode. Also it lacks Gamma correction. 195.35.160.133 (talk) 10:38, 26 January 2010 (UTC) Martin.

Thank you. Cuddlyable3 (talk) 00:46, 25 January 2010 (UTC)

Graphics in BASIC (2)

Resolved

My graphics programs written in Borland Turbo BASIC worked on every PC until I used Vista Home Premium. This OS refuses to show VGA graphics and warns "This system does not support full screen graphics". A) What can I do? B) Is the article Video Graphics Array wrong to say VGA is (as of 2009) the lowest common denominator that all PC graphics hardware supports" ? Cuddlyable3 (talk) 12:09, 19 January 2010 (UTC)

I suspect your hardware supports VGA, but Vista won't allow direct hardware access to VGA. 195.35.160.133 (talk) 13:15, 19 January 2010 (UTC) Martin.

(A) Have you tried setting the properties of your compiled app such that Vista thinks it has to run it in Windows 95 Compatibility Mode? (B) I put a fact-tag on that sentence in the article because it is unreferenced. I have no evidence but would suspect that all graphics boards in current production support at least 640x480, 256-color Super VGA, or even 800x600; I would be quite shocked to find a current graphics board that doesn't support those two. Alternatively, it might be wrong if a demented hobbyist somewhere is still making EGA graphics boards. Comet Tuttle (talk) 17:32, 19 January 2010 (UTC)

I installed DOSbox and now I can show my full screen VGA graphics. Cuddlyable3 (talk) 17:46, 30 January 2010 (UTC)

is JSP a Servlet?

is JSP a Servlet?

Assuming you mean JavaServer Pages then "Architecturally, JSP may be viewed as a high-level abstraction of Java servlets." (from the article).87.102.67.84 (talk) 13:35, 19 January 2010 (UTC)

JSP is a technology, encompassing a programming meta-language, a compiler integration technology, and a set of standard practices for installing on a web server. A servlet is a specific compiled incarnation of a specific program that conforms to certain specifications. JSP can be used to generate servlets - these technologies are commonly used together and integrate well. Servlets can also be compiled directly from Java source code, without ever writing JSP. JSP can also operate a dynamic web page without ever compiling a servlet, but this is uncommon. Nimur (talk) 20:18, 19 January 2010 (UTC)

Crack search engine

What is it? Kittybrewster ☎ 15:39, 19 January 2010 (UTC)

It usually refers to a search engine of software cracking tools—used for pirating software, games, etc. The cracks are programs that modify the original program in order to eliminate its copy-protection schemes. I suspect they have gotten a lot less necessary for pirating these days, as it has become more common to just download the entire, cracked program available via torrent websites. But back in the day, you could borrow a disc from a friend, download the crack (usually a very small file), and use that to install it, even if there were copy-protection schemes. --Mr.98 (talk) 15:56, 19 January 2010 (UTC)

You may be thinking of Astalavista.box.sk, but I can't say that I recommend it. Make sure you've got good virus protection. APL (talk) 16:49, 19 January 2010 (UTC)

I found it by searching for terrapin ftp which led me to the word "crack" and I couldn't see the connection. Kittybrewster ☎ 17:33, 19 January 2010 (UTC)

Nowadays crack engines are full of viruses, adware, etc. The days of cracking your own software are pretty bygone at this point. --Mr.98 (talk) 17:52, 19 January 2010 (UTC)

Finding cracks via google is easy —Preceding unsigned comment added by 82.43.91.83 (talk) 18:34, 19 January 2010 (UTC)

Finding things that look like cracks but are actually viruses is also easy. APL (talk) 22:19, 19 January 2010 (UTC)

But it's how I make a bit of cash cleaning Vundo and the rest of the crap. Last customer was honest enough to tell me that he downloaded a keygen. ---— Gadget850 (Ed) ^talk 22:51, 19 January 2010 (UTC)

Serpentine Gallery

Does anyone know how to change the contact details for the Serpentine Gallery?

I have been trying and cannot get my head round it?

The correct address is:

Kensington Gardens London W2 3XA

NOT

Queensborough Terrace, Paddington,

Please help???? —Preceding unsigned comment added by Serpentine gallery press dept (talk • contribs) 18:16, 19 January 2010 (UTC)

There is no contact information in Serpentine Gallery. It appears that you are concerned about the coordinates. They are not based on an address. It is the latitude and longitude of the gallery. Many mapping services will show an address when you give it a lat/lon coordinate. That address may be wrong - but it has nothing to do with Wikipedia. -- kainaw™ 18:21, 19 January 2010 (UTC)

Google seems to be the thing that has it wrong. Frankly, I'd recommend you talk to their PR people, who might have a better chance of routing an enquiry to someone in the organisation who has a clue. Wikipedia's geographic coordinate for the gallery is spot on and is not the cause of the issue. --Tagishsimon (talk) 18:35, 19 January 2010 (UTC)

The Serpentine Gallery article does have the correct coordinates. Quite why Google has it wrong is puzzling, but I did click on the "Is this accurate?" link provided in the Google search. Astronaut (talk) 02:18, 20 January 2010 (UTC)

WLAN problems

Until recently, I used an XP laptop on a WiFi network. The router was connected to an XP desktop, which had a printer. I could print fine, and access files fine, but if I tried to drop any files from one to the other, the WiFi connection dropped immediately.

Now I have a Windows 7 laptop, and the same happens, plus the fact that I can't print from a PDF file (MS Word prints fine etc.) - what could be the problem? Thanks! ╟─TreasuryTag►belonger─╢ 22:18, 19 January 2010 (UTC)

Sounds vaguely familiar. What is the router brand, model and firmware? ---— Gadget850 (Ed) ^talk 22:48, 19 January 2010 (UTC)

It's a Zyxel... would P-660HW-T1 v2 be the brand number? ╟─TreasuryTag►sheriff─╢ 22:54, 19 January 2010 (UTC)

Never played with Zyxel (and I have tested some odd stuff). There is a P-660HW-D1 v2. Looks like the latest firmware is V3.40(ATA.0)C0 | 3/28/2007— you will have to open the router web page to get the firmware revision. I looked at the rev notes in the download (marked company confidential?) and there is nothing obvious; but it is in Engrish and in my experience, engineers are horrible at documenting changes. I do suspect the router— couldn't hurt to ensure you have the lastest firmware and do a reset. Otherwise, routers are relatively cheap. ---— Gadget850 (Ed) ^talk 23:12, 19 January 2010 (UTC)

Eurasian telephone country and area code

What geographical information is in the following telephone number?

007077226…and then three digits which I omit for privacy

As far as I understand, 007 is Russia and Kazakhstan, and the following zero is perhaps somehow not part of the area code, but inserted for all international calls (if so, wouldn't that make the country code +70 instead of +7?), but I failed to find any area codes starting with 77 (or 077) in lists of area codes: kasach.de, Rostelecom, Kazakhstan (Казахстан), Russia (Россия)

So, is it a special number (mobile phone? secret service? god?), or did I get something wrong and it's a normal place like eastern Kazakhstan or Almaty? 23:37, 19 January 2010 (UTC)

I assume by the wording in your question that you are located outside of Russia and inside Europe, so your international dialing prefix is "00". Is that correct? Also, are you sure this is exactly how the number was written (i.e. are you sure the "007" is a country code and prefix as opposed to part of a local number)?

The reason I ask is because the number you give is also one digit short. Normal Russian phone numbers are 10 digits, in the format (NNN) XXX-XX-XX after you remove the country code and prefix. In addition, no Russian phone number has an area code starting with 7, and Kazakstan's area codes all seem to be 71x or 72x. Xenon54 / talk / 01:15, 20 January 2010 (UTC)

Thank you. Yes, I am in Germany, and I've given the number as displayed in the phone (somebody called in the early morning), minus the last 3 digits. I'm not sure but I don't think there's anything that starts with 00 except calls from/to abroad. The phone always shows calls from abroad as 00, followed by the country code. The easiest thing would probably be to call back and ask, but that's expensive and requires a common language. Somebody must have dialed the wrong number, but it itches me that whoever it was seemingly called from nowhere. I've added another list of Kaz. area codes to my original post. 84.46.48.150 (talk) 01:32, 20 January 2010 (UTC)

Hmm...interesting. Germany's phone numbers are 10 digits, correct? Continuing the theory that the caller is from Kazakhstan: perhaps the mysterious caller's number was too long to display properly. Try going to yellowpages.kz (in English, surprisingly) and typing in the number beginning from 226, leaving the drop-down at any city. See what comes up. If you don't get any results (because the linked website is "yellow pages" and thus businesses only) that doesn't rule out the number being a residential area, but as there are no white pages for the country you would be out of luck. Xenon54 / talk / 02:07, 20 January 2010 (UTC)

How it used to be is like this: '00' is the international access code in use in most countries, '7' is the code for Russia. Unlike most countries, Russia did not drop the leading '0' from area code; so '077' would be the area code of a city somewhere in Russia. However, according to Telephone numbers in Russia, there have been many changes including the replacement of area codes with a leading '0', so the '077' could be an obsolete area code. The international operator here in the UK confirmed that the leading '0' is no longer needed.

The operator did propose another theory though, that the number is infact a UK mobile and someone has added the '007' international code to Russia thinking that it is needed if the person is visiting Russia (it isn't - just enter the number as if they were still at home). However, I did notice that if that was the case there are too few numbers for a UK mobile. Perhaps this is nothing to do with Russia at all and it's just a UK mobile number with an extra zero on the very front. Or perhaps it is nothing to do with UK mobiles but another country's mobile service (one that uses only 9 digits). What happens when you call? Astronaut (talk) 02:06, 20 January 2010 (UTC)

Actually, since they called you the caller's number should appear to come from a real place. I think the only way you are going to find out is to call them back. TBH is is likely to be a wrong number - if they really want to speak with you, they'll probably call again. Astronaut (talk) 02:08, 20 January 2010 (UTC)

And if it is a UK mobile number, use caution - 07077 mobile numbers are 'personal' or 'vanity' numbers and some are used under the PN2 system which have the ability to be diverted anywhere in the world, some of the cost of which is charged to the caller. Nanonic (talk) 02:14, 20 January 2010 (UTC)

Thank you people for your efforts, I didn't expect anyone to go to the trouble (and cost?) of calling and asking an operator! You're a very helpful bunch! To Xenon: When this phone truncates numbers for display, it attaches a "…" in front of what fits in the display to indicate removal of the first digits. I tried your yellow pages, which showed no results for the exact number and likely variants, but showed a few numbers in Almaty and Astana starting with the first four digits (226X). What I know about German phone numbers is this: I dial 0+four digits for my grandmother's village and three digits for her house, newer lines have longer numbers. The city I live in has 0+two digits area code followed by a number of six to eight digits of which the first must not be 0. To Astronaut: The caller called on 2009-01-19, so they couldn't have used an obsolete code. The German counterpart to the UK's 070 numbers are 0700 numbers. I've checked several times, and the number at hand does not start with 070…, but with 0070… as given above. I haven't understood the operator's theory, but if it were a UK number, wouldn't my phone show 0044… as it does with simple landline callers? Not sure about this, though – I don't think I've ever had somebody call here from a special personal/vanity number. Oh, and a UK person probably wouldn't have called between 5 and 6 am. To Nanonic: Since it doesn't look like a UK number to me, I might try VoIP later to call our mysterious caller back. Will post result here. If it's god, what should I ask? 84.46.48.150 (talk) 02:58, 20 January 2010 (UTC)