I have been developing using a single 15.4" laptop for a while (duh!). Actually I am quite comfortable. I use compiz Grid, scale, window and some other nice add ons, to easily navigate.
I am now impressed by other dual monitor related questions on Stackoverflow and am buying more monitors.
Since I am not exactly used to these multiple monitor setups, I have a few (possibly basic) queries.
If I buy just one monitor, will I be able to set up it for a different resolution than on my laptop, on Ubuntu. What packages I need to install on ubuntu to better manage multiple monitors.
If I buy 2 22" monitors and intend to use the laptop screen as well, wont the third one appear like an odd man. Does it happen even if I have just 2 monitors.
I have used Dell and HP monitors in my earlier company and I feel HP is so much better. Obviously I would love to have a monitor that has little corners and nearly all visible screen, like iPhone. Is there a specific recommended model.
For a 3 monitor setup, is it absolutely necessary to buy an extra graphics card. Are there any other better solutions.
You can have two monitors at different resolution on Ubuntu just fine. I used to connect an Ubuntu laptop to a TV using HDMI and it worked fine. Something annoying is what monitor gets to be the main one, because you get all your desktop there. I thing generally the biggest one is the main one, which is not what I wanted for the TV, but probably what you want.
I'm not sure if it's possible to get a third monitor in any way on a laptop. I'd recommend you to go for the biggest monitor you can (budget and laptop capabilities, can you go to 30"?) and use the laptop as secondary screen space (useful for a browser, or docs, or im/tweeter/mails, etc.
A CRT monitor can be set up with most any resolution you like, while a LCD monitor works best at it's max resolution.
You can mix monitors with different resolutions without problems in Windows, I can't imagine that it would be very hard in Linux either.
Be carefully dual head on Linux still sucks. The only time i got a triple screen configured with a GUI frontend and without .XConfig hacks was with Mandriva Spring 2007 never before and never after with any of Suse, Mandriva, CentOS.
It really sucks. It seems that configuration like dual head on one card and single head on another one is just not in the head of the programmers. You can enable all cards (maybe dual head is not always supported) or none.
Windows and MacOSX are the only systems which work fine. But MacOSX (and Hackintoshs) do not support dual head on all supported cards, for example my two 7300GTS cards can't run as dual head on MacOSX.
Related
I live in a building where the laundry machine is a bit far away from my suite. There is only one machine there so only one person can use it at a time. Quite often I take my laundry there just to realize that the machine is in use so I have to go back defeated and try again later. I want to build a doodad that can detect when the machine is in use and broadcast that information throughout the building so that I know that the machine will be available before I go there.
This question is not about how to build the detector. I am planning on using a raspberry pi somehow. This question is about what do I do when I detect that the machine is in use. How do I broadcast that information mainly to myself or potentially to anyone in the building?
I need a cheap solution (< $100). It has to be wireless. The signal has to travel approximately 30 meters in one direction. The broadcast should be readable on any laptop or cell phone (not a requirement but nice to have).
I was considering making an android app using WiFi direct. I'm sure others in the building would be interested in this app and I can use them as peers to extend the range of the broadcast. But I don't like this solution because I know that wifi direct doesn't work with iOS devices. Also this solution will require others to side-load an apk which they might not know how to do.
Please let me know if you can come up with something a bit less reliant on p2p and more platform independent.
I'm new to VMWare and want to use VMWare to implement some networking examples(mainly just networking between two computers, and testing out some self-configuration and failsafe abilities). Also to possibly test out some failsafe capabilities of the Oracle Database.
I'm just not sure if I need to pay up $99 for the VMWare Player Plus , or am I Ok with just getting VirtualBox(free) or simple VMWare Player?
Overall I'm new to the Virtual-Machine arena, and I hope I can get some pointers on how to use these tools.
thank
Start with VMware Player. If it doesn't provide what you need you can look into a paid solution.
My guess based on the information you provided is that Player/VirtualBox will be sufficient for your needs.
One note on Player - you can launch multiple instances. It isn't terribly obvious and not laid out like Workstation/VirtualBox with an instance list/tree on the left.
I want to port a good OpenCV code on an embedded platform. Earlier such stuffs were very difficult to perform but now TI has come up with nice embedded platforms which are comparatively hassle free as they say.
I want to know following things:
Given that :
The OpenCV code is already running on PC smoothly. (obviously)
Need to determine these before purchasing the device.
Can't put the code here in stackoverflow. :P
To chose from Texas Instruments: C6000.
Questions:
How to make it sure that the porting will be done?
What steps to be taken to make it sure that after porting the code, will run (at least).
to determine whether the code might require some changes to make its run smooth.
The point 3 above is optional.
I need info which will at least give me some start up in this regard.
What I thought I should do?
I am to list the inbuilt functions down.
Then to find available online bench marking for those functions for the particular device like as shown towards the end of this doc.
...
Need to know how to proceed further?
However C6-Integra™ DSP+ARM Processor seems the best.
The best you can do is to try a device simulator (if it is available), but what you'll see there is far from perfect.
Actually, nothing can tell you how fast and how well the app will run on the embedded device before running you specific app on that specific device.
So:
Step 1 Buy it
Step 2 Try it
Things to consider:
embedded CPU architecture: Your app needs a big cache? how big is the embedded cache?
algorithm: do you use a lot of floating point operations? how good is the device at floating point ops?
do you have memory transfers? data bus on a PC is waaay faster than on embedded
hardware support: do you use a lot of double-precision calculations? they are emulated on ARMs. They are gonna kill your app (from millisecons on a PC it can go to seconds on a ARM)
Acceleration. Do your functions use SSE? (many OpenCV funcs are SSEd, even if you don't know). Do you have the NEON counterpart? (OpenCV does not have much support for that). The difference can be orders of magnitude from x86 SSE to embedded without NEON.
and many, many others.
So, again: no one can tell you how it will work. Just the combination between the specific app and the real device tells the truth.
even a run on a similar device is not relevant. It can run smoothly on a given processor, and with another, with similar freq or listed memory, it will slow down too much
This is an interesting question but run is a very generic word in this context, therefore I feel the need to break it down to other 2 questions:
Will it compile in an embedded device?
Will it run as fast/smooth as in a PC?
I've used OpenCV in a lot of different devices, including ARM, SH4, MIPS and I found out that sometimes the manufacturer of the device itself provides a compiled version of OpenCV (for my surprise), which is great. That's something you can look into, maybe the manufacturer of your device provide OpenCV binaries.
There's no way to know for sure how smooth your OpenCV application will be on the target device unless you are able to find some benchmark of OpenCV running in there. PCs have far better processing power than embedded devices, so you can expect less performance from the target device.
There are 3rd party applications like opencv-performance, that you can use to test/benchmark the environment once you get your hands on it. And if performance is such a big deal in this project, you might also be interested in this nice article which explain some timing tests done on couple of OpenCV features comparing implementations using the C and C++ interfaces of OpenCV.
Is there an official way for an application to determine if it is running in VMWare or Virtual PC (or whatever Microsoft is calling it now)? The code I have seen is usually a hack that took advantage of some odd behavioral side effect in a specific version of VMWare or Virtual PC.
Ideally Delphi code, but if you can link to an official explanation then I am sure I can convert it.
I wrote a series of articles last year on this, with source code. VMware and Wine detection are here. Virtual PC is here. All three of these have pretty iron-clad detection because there are documented callbacks to the hypervisor (in the case of Wine, an extension to a standard DLL). I put up an untested VirtualBox detector (don't have it installed to test with) in the comment section. Parallels might be detectable using a callback also but I don't have it installed. The link for the documentation (which is poor since it's from a security researcher focusing on exploits) but located here if you have it installed and are interested. There's also a PPT here that has some information on detecting Sandbox, Bochs, and Xen. Not a lot of code in it but it might give you a starting point if you have to detect those.
Code Project shows a way to Detect if your program is running inside a Virtual Machine that goes in much detail on how to accomplish it to give a good understanding
I think the best approach to this is to check the hardware profiles. Virtualized hardware usually uses part of the companies name. If you check the motherboard description while in Virtual PC, you will notice it is made by "Microsoft Corporation". Likewise in VMWare, your ethernet adapter will be prefixed with VMNet.
This thread on the SysInternals forums has a couple of answers (in Delphi, of course), including a single IsVM function. I've tested on XP and Win2003 hosted on both XP and Vista in VMWare with good results.
There is a WMI way posted here:
http://blogs.msdn.com/virtual_pc_guy/archive/2005/10/27/484479.aspx
I've double checked in an XP image running on Virtual PC, and the value they're testing for is still the same. I won't guarantee what other VMs return here, though...
I've actually got a Delphi program I wrote a couple of years ago to get a list of and change the default printer using WMI, without requiring 3rd party components or anything like that. In case you're not used to working with WMI from Delphi, I can send you a copy so you have something to work off (it's not necessarily Unicode-compatible, though, but it shouldn't be too hard for me to upgrade it if need be).
I used the RedPill method (translated to Delphi, but the code isn't that hard to understand) which worked fairly well. I also included a few extra checks using WMI calls to get things like the network adapter vendor name and copyrights, but that was for detecting specific versions of Virtual PC.
My understanding of the RedPill method is that it should work and detect all virtual machines based on the nature of how it works. There is the possiblity that false positives might be generated also as the new Windows within Windows feature of Windows 7 can be configured to run selected programs in a copy of Windows XP seamlessly inside Windows 7.
I've had good luck with just looking at the MAC address as all manufacturers are given a block and the first 3 parts are unique to them.
//look at the MAC address and determine if it's a Virtual Machine
$temp = preg_split("/\s+/",exec("/sbin/ifconfig -a eth0 2>&1 | /bin/grep HWaddr"), -1, PREG_SPLIT_NO_EMPTY);
//Virtual Box MACs all start with '08:00:27:xx:xx:xx'
if (strpos($temp[4], '08:00:27') !== false) $_SESSION['DEVELOPMENT'] = true;
To determine the machine is physical or VM
dmidecode | egrep -i 'manufacturer|product'
If the dmidecode command not found install the respective rpm.
This is tested under EXSI, VMWARE and hyperv machines.
dmidecode -s system-product-name
Tested on VirtualBox, result:
Virtualbox
If you want to generally detect the presence of any type of virtualization, you are best analyzing performance characteristics. Take something that is significantly slower in virtualization (such as MMU heavy workload like a fork-bomb) and time it against a normal CPU bound user space app. From the ratio you can easily tell.
Easiest in terms of effort if you only care about certain VMMs is to look for their hardware- i.e. VMware PCI devices:
00:07.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 08)
Subsystem: VMware Inc Virtual Machine Chipset
15ad:1976
The vendor value is '15ad'
There are also specific backdoor ports that work across various VMMs in various versions. SIDT trick is good too, but what if a VMM is not on the list that his code is checking?
Where would you recommend that I find a company to develop or buy a CD/DVD loading arm similar to: http://www.dextimus.com/
Preferably programmable via USB but if I only can get one with a serial interface that would be fine. Drivers dont matter - I can interface directly with the unit as my situation is very unique.
If you have some experience with electronics, you can give it a shot and build it yourself, like this or this.
I should add that the schematics and the source code are included, and in more details in the first project.
I suppose I might just shorten this by giving a list of resources first:
http://www.embedinc.com/ I trust this company to do good work. Expensive (actually, they are reasonably priced in the design community, but would be considered expensive by most hobbyists and individuals). Not great at people skills, but very very very good at what they do.
You should check out the various microcontroller communities and forums for hobbyists and professionals that can do this. Search for microchip, atmel, msp430, arm, powerpc, etc.
Sparkfun is a supplier to the electronics community - they have great forums where you can post your request, and you'll find people who might do it for fun with only the cost of materials. Might take longer, might not be as 'professional' or well packaged and delivered, but it might be your best low cost option.
There are many electronic design companies that could do this (for instance, I can do this sort of thing).
But there are many questions you haven't answered (and may not have researched) that could prevent success:
Is this patented?
What CD loading/unloading methods are not patented, are out of patent, or otherwise available?
What is your design goal - a one off just for you, or a device that can be built in the hundreds for industrial use, or a device meant for general office workers/consumers that is built in the millions?
Do you realize that this design qould surely cost mroe than simply buying one, if one is all you need?
As an example, assuming you don't need the nice enclosure and don't mind a 'prototype' look, just the mechanicals, electronics, and firmware design (no software on the PC) would likely be 100-250 billable hours for a design firm. At a cheap $90/hr, that's $9k to nearly $25k for one prototype. Add PC software and the nice enclosure, etc and you'll double that.
If you can find a local 'Make' group (techshop, GoTech, or similar) then you might be able to find a hobbyist that is willing to play with this idea for the cost of materials.
But if you define what your goal is, and give us an idea of your resources you may find a better answer.
-Adam
You can create a very nice simple solution using radio control servos. They come in many sizes, but even the small ones have enough torque to move a big arm to move a cd.
The real bonus with servos is that they normally have 180 degrees of rotation and internally have a variable resistor (rheostat) for positioning feedback. Positioning accuracy is normally within 1 degree of rotation which should be fine for a cd loader.
For picking up the CDs, nothing will beat a vacuum. I recommend a small battery powered vacuum cleaner. Funnel the suction into a 1/4 inch pipe. At the other end of the pipe a one inch diameter cup should provide more than enough lift from the small amount of suction.
As for the pile of blank CDs to be burnt, I would advise in moving the pile up rather than an arm down to it. probably having the top blank cd about 1/4 inch higher than the cd tray - By doing this, the arm only needs to rotate in one axis and the vacuum should be enough to suck the cd back out of the tray.
Now, for the electronics. For the servo control I suggest an rs232 serial servo controller. I've used the one from http://www.basicx.com/Products/servo/servo8t.htm as it also gives back torque information from the current draw.
For the low sample rate digital i/o, i suggest (for windows) inpout32.dll which is a dll to give you direct access to the bits of a parallel port. This will allow you to turn on the vacuum at the correct time and possibly sense when cd's have run out. Note that a parallel port can sink more current than it sources so for outputs you should connect to the 5v power line and set the output pin to 0 to turn on the output and 1 to turn it off.
The other nice option, which is very, very simple to interface and very cheap is to get hold of a picaxe from http://www.rev-ed.co.uk/picaxe/. These use a very simple programming language (a BASIC spin off) allowing you to read serial data in and control the servos and digital I/O on one chip. Last time I used one, the language was a bit simple - if statements had to jumped labels, else didn't exist.
If you do use a microcontroller and servos, it is best to use a dual voltage power supply as servos are noisy and can cause the microcontrollers to reset.
As for switching loads such as the vacuum on, you'll need to use a mosfet or (if money is no object) the simpler option, a solid state relay.
All digital inputs you use on the microcontroller should be pulled either to +V or ground with say a 5k resistor so they never float.
I cannot stress how simple and cheap the picaxes are. They have a built in interpreter so although code space is minimal on the small 8 pin units, they are programmable via a simple serial lead.
Good luck. Once you get into automation control, you'll never be able to stop. I'm in the middle of building a 3 axis CNC router so I can cut parts for other projects (I tell my girlfriend it's so she can cut out xmas decorations!).
You might want to contact Aaron Shephard about his Florian project.
I've found that a really easy board to control stepper motors or sorvos are produced by phidgets - the API is incredibly easy, and available for a vast array of platforms.