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Laptop as Guitar Interface Part -3

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Setting up the Amplitube: Usually u can select the prebuilt presets.... some worked well for me .. some were noisy .I will guide u 1 clean and 1 distortion preset that worked for me well .A good cable is very(!) important..as this laptop mic interface is very sensitive else u will get lott of buzz , hummmmmmmmmmmmm.. In both preset the EQ cuts the excess bass that hinder the sound, u may have to fiddle a little with ur guitar .. Remember : always keep the Guitar volme 30% lower than max .. else some sensitive pickups may damage the laptop card. If u wanna real good interace takea professionnal card like the MAudio guitar interface ... comes abt 4k INR. My-Clean: amp:American tube vintage cab : default rack: default Stomp: select EQ1 and EQ3 (third position) i keep echoman for some songs My-distortion: amp:modern tube lead cab : default rack: default Stomp: select EQ1 ,overdrive and EQ3 (third position)

Laptop as Guitar Interface Part -2

Software setup : Start amplitube , go settings>Audiosetup>select Asio...leave all others default. Now setup asio driver: ASIO4ALL v2 Instruction Manual it is a big document ... practically u just need to select 128frames setting in ASIO panel,( double click on the green icon. )

Laptop as Guitar Interface Part -1

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Despite of the fact that web -o-pedia is all about embedded devices , inter faces This time it wil differ slightly from all those tech stuff... seriously ! it is all about making music , and the electric Guitar . the one remarkable instrument that went unreplacable no matter what synth devices the modern technology has given us .. Ok coming to the point , today we will setup the LAPTOP(u can use pc,if u must ) to be a effect processor , padal boards... with unlimited number of presets , as well custom ones. U need 1> Amplitube ... get a patched version via torrent 2> Asio4all driver..http://www.asio4all.com/ needed as normal windows driver cant catch guitar signal fast >cable and amp setup first install the Asio4all 3.5mm to guitar jack cable u need plug the lappy as shown below

what are static variables and globals

In c programming static variable is a special type of variable can retain its value between invocations .It has two types : 1. Static to function or control block 2. Static to the file If it is static to function it will retain the value when the function is called again and again . Eg Void foo() { Static int a; a++; printf(“%d\n”,a); } In consecutive calls it will have values 1 , 2 ….. But cant be accessed outside of the function. In the static to the file scenario the variable is commonly declared at the top like the globals . it is accessible to all functions but it will retain the value. Difference between the globals , when static is in a header file it will have 1 copy per file that include the header. Eg: -----------------test.h----------------- static int var; ----------------- mainfile.c ---------------------- #include #include ”test.h” Int main (){ printf("var in %s: %d\n ", __FILE__, ++var); in_file2(); } ----------

Constant volatile variable

Can you have constant volatile variable? You can have a const volatile variable. Its syntactically correct and often used while expecting a value change from the hardware. Example: The status registers (read only) if micro controllers are often declared as const volatile statRegxxxx; The program (software) shouldn't change the value of statRegxxxx, only the hardware can

volatile variables ? example

In embedded we deal with special features in c language that are provided to make building systems convenient. One such feature is volatile variable : A variable should be declared volatile whenever its value could change unexpectedly viz by external influences like the variable representing memory mapped peripheral register. Example: static int var; void test(void) { var = 0; while (var != 255) continue; } The above code sets the value in var to 0. It then starts to poll that value in a loop until the value of var becomes 255. An optimizing compiler will notice that no other code can possibly change the value stored in 'var', and therefore assume that it will remain equal to 0 at all times. The compiler will then replace the function body with an infinite loop, similar to this: void test_opt(void) { var = 0; while (TRUE) continue; } solution is : volatile int var;

How to reverse engineer USB device

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Snooping the data transfer in USB under windows is a way to develop USB drivers . The devices with unavailable specs can be examined in a free ware called SnoopyPro . Here is how : 1.Unpack and Install File->Unpack Drivers and File->Install Service 2. get the device address from windows device manager 3.select the end point you want to snoop..... tada you will see wahtz going on . In the image we have selected a keyboard device with VID 534b and snooping on the second end point (0x01) . Here is the cool log at your diposal.

Enjoy HD in OLD laptop in 20$

As i came across the news of the release of The BCM70010/BCM70012 chipset ...i am very excited to revive my P4 pc .. What is this chip and how it is useful : Broadcom chip uses Crystal HD Enhanced Video Accelerator solution. So your old laptop/PC or even ARM miniPCI devices you can revive with a card that has this chip. Most interesting part is the cost just 20$ <1000Rs.. so grab one and use. These are selling via ebay India: http://cgi.ebay.in/ws/eBayISAPI.dll?ViewItem&item=320436937576 or you can try ebay.com if you have paypal. This introduces the advantages of next-generation high definition H.264 and VC-1 video compression algorithms to netbook and nettop applications like the playback of streaming media and downloaded media as well as Blu-ray™ discs. The chipset is a single-stream HD AVC/VC-1/MPEG-2 decoder solution capable of full HD real-time decoding. The high performance and low power consumption of the solution allow reduced CPU utilization and support fo

My Hot Air Pencil in Rs 300 for smd

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ARM9 soldering problem is solved.. i made the hot air pencil. See pics and details are ... Parts needed : 1 cheap soldering pipe shaped ,coil heater type:140/- like this http://www.hvwtech.com/products/206/44100_PV.jpg 1acqurium pump + air pipe :130/- 6 inch pneumatic tubing :30/- like this http://ecx.images-amazon.com/images/...500_AA280_.jpg (my innovation it withstands approx 100deg, at the coupling end the temp does not go v high). Super glue , paper etc.. How to : 1.rip apart soldering iron, remove metal tip. 2.Leaving the front hole (where metal tip was there) cover the other holes with 2 layer of paper put duct tape to make the paper hold.This is to prevent air leak. 3. connect air pipe to the 6" pneumatic tubing seal the joint with superglue,put the other end of the tubing to soldering iron metal pipe. with paper as insulator. 4. Close the soldering handle with pipe and wires mine is taped to hold together."Be careful not to short mains wires".My iron had fully i

ARM9 Board Taking shape -2:Active parts

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See the power IC how small it is , I will have to make a HOT AIR PENCIL. There are 20+ web sites detailing it but I will use my way to do that.. Done the shopping by now. I will create a post on the same soon.

LED desktop thingy!

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I bought a china made LED torch cum table lamp. Costed very less. Charges well gives 8Hour backup minimum(did not check when it goes off) from a 6hour charge What is special here is it is a torch with a flip 6ultrabright LED panel.The panel tilts at 15degrees , so you can point the LED sets all directions... that is too much the price of 1 cup coffee in some places .Panel can be hidden when used as torch. But there is a problem! The table light /torch loses the intensity after 3hours to 60%. There must be a way to keep intensity same. I needed a constant current source at least 0.5A. I searched on net and got (LED driver) : http://www.candlepowerforums.com/vb/showthread.php?t=236260 image: And I know about joule thief circuit ->simple 1 or 2 transistor circuit increases the voltage. Here is joule thief: (i assume battery is 6v ) Plan is : battery(6v)>joule thief(9v)>LED driver>LEDs smooth white light till battery loses the charge (if backup become 6Hrs , fine na!)

Arm9 board free samples locked up

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I am asking free samples from a company , for atleast the power section some one named Srikanth G. from their local office ,locking the samples and asking business details again and again . Samples save good $$$. If not i have 10 other alternatives. Letz see what comes out . Board is in progress , 90% of components supply i sorted out. The At01 series has inbuilt loader that will init the chip and peripherials. Now i need to learn the 1st time flashing of the Uboot loader. SD RAM I got : see it on the board before soldering Update: sample will be most probably be released , as i convinced them . Local center guy i forced putting mail to HO. hahaha :). One problem is there: The SDRAM pads are too small ,go under the chip legs.manual soldering will be tricky. UPDATE: IC Pack and samples have arrived , flash,eeprom,power sections things came . from usa, mainchip and ethernet chip has to come from Taiwan and Hong Kong. Look at the Flash IC box , well packed in antistatic box

ARM9 BOARD TAKING SHAPE-2 :passives

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This is phase 1: I am at my office where i work as consultant ..whoa !today passive components have arrived.Means the resistor and capacitors 0402size. The size presented a hurdle, 0603 components are pretty easy to get . But finally i got hold of the components. more are there in my tray shelf . I got passive s for 10 boards for trial build we will take chips 1 pc each . Let the prototype be ready as well toolset .. then may go bulk. phases of build : Phase 1: Passives arrives + jacks etc {done} Phase 2: Active cmp arrives mainly At91rm9200 Phase 3: Solder and test

ARM9Board ...taking shape 1

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The ARM9 board taking shape , at office I got a delivery of 20 PCBS recently... well built FR4 laminate .Green masking applied on both sides , Silver coated pads and vias . Thanks to my contacts in product industry .. However the sourcing of the chips is still critical .I am working on it So far i have been in touch with many middleman Letz wait and see...

My ARM9 Development board for indian developers

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The Low Cost ARM9 board is here . I always wanted to bring a low cost solution for indian developers . A highly capable ARM9 board that can run embedded realtime linux . with ample amount of memory and provision for future expansion. Now! Why to pay 40 k for an ARM lab setup with JTAG and all ...my design is just <6K Rs. The design criteria is fulfilled with AT91RM series ARM9 chip based design . Added 256MB sdRAM,64MB flash,24LC512 eeprom, can, JTAG , USB serial interface( for laptops this is handy as there is no serial port ), CAN bus transiever, controller . It has a USB host too! there are more interfaces can be added . There are many online ported versions of linux for the chips as well as develeoper forums /Groups . Designed during off time and now almost ready : See the snaps of it : After working 4 years in embedded product domain , i felt the need of hardware test setup for learning board level porting, device drivers BSP development. As well as a board that is suit