Thursday, May 14, 2009

MODEM

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TCM Trellis-Coded Modulation (with Viterbi coding) is anoptional error-correction method included in the V.32 standard. TCM allows modems to check for transmission errors with aredundancy bit, which results in fewer errors on noisy lines. Trellis Encoding works WITH other error correction methods suchas V.42. Unlike other methods, TCM is true error correction, inthat for small errors, it does not force a retransmit, itactually fixes them. MNP - Microcom Network Protocol is a set of standards developedby Microcom, and made available by them to other manufacturers.

MNP Class 1 is referred to as Block Mode. It uses asynchronous,byte-oriented, Half-duplex transmission. This method providesonly about 70% efficiency, and is rarely used today. MNP Class 2 is called Stream Mode, and uses asynchronous, byte-oriented, Full-duplex transmission. Because of protocol overhead(the time it takes to establish the protocol and operate it),throughput at Class 2 is actually only about 84% of that for aconnection without MNP, delivering about 202 cps (characters persecond) at 2400 bps and is rarely used today.

MNP Class 3 incorporates Class 2, and is more efficient. It usesa synchronous, bit-oriented, Full-duplex method. This procedureyields throughput about 108% of that of a modem without MNP,delivering about 254 cps at 2400 bps. MNP Class 4 uses Adaptive Packet Assembly and Optimized DataPhase techniques, it improves throughput and performance by about5%, although actual increases depend on the type of call (noisyor clean), and can be as high as 25% to 50% on some links. V.42: is a CCITT error-correction standard that's similar to MNPClass 4, In fact, because the V.42 standard includes MNPcompatibility through Class 4, all MNP 4- compatible modems canestablish error-controlled connections with V.42 modems. Thisstandard, however, prefers to use its own better performingprotocol .

LAPM Link Access Procedure for Modems, like MNP, copes withphone line impairments by automatically re-transmitting data thatis corrupted during transmission assuring that only error freedata passes through the modems. LAPB : Link Access Procedure Binary, like MNP or LAPM, copeswith phone line impairments by automatically re-transmitting datathat is corrupted during transmission assuring that only errorfree data passes through the modems.

CORE PROCESSOR

This section describes the main features of the OMAP5910 device, lists the terminal assignments, and describes the function of each terminal. This data manual also provides a detailed description section,electrical specifications, parameter measurement information, and mechanical data about the available packaging.


The OMAP5910 is a highly integrated hardware and software platform, designed to meet the application processing needs of next-generation embedded devices. The OMAP platform enables OEMs and ODMs to quickly bring to market devices featuring rich user
interfaces, high processing performance, and long battery life through the maximum flexibility of a fully integrated mixed processor solution.

The dual-core architecture provides benefits of both DSP and RISC technologies, incorporating a
TMS320C55x DSP core and a high-performance TI925T ARM core.
The OMAP5910 device is designed to run leading open and embedded RISC-based operating systems, as well as the Texas Instruments (TI) DSP/BIOS software kernel foundation, and is available in a 289-ball MicroStar BGA package.

The OMAP5910 is targeted at the following applications: Applications processing devices, Mobile communications Bluetooth wireless technology GSM (including GPRS and EDGE) CDMA Proprietary government and other Video and image processing (MPEG4, JPEG, Windows Media Video, etc.) Advanced speech applications (text-to-speech, speech recognition) Audio processing (MPEG-1 Audio Layer3 [MP3], AMR, WMA, AAC, and other GSM speech codecs).Graphics and video acceleration.

MOTHER BOARD

Here is a list of "things you should know" about upgrading your IBM or clone computer. I am going to focus on upgrading with a numeric co-processor, a math chip. And, whether or not you really need to upgrade to the latest 80486 system even if you think you are maxed out on your 33 Mhz 80386.

Even if you are familiar with the 80x87 series read on. Now there are alternative clone chips. One of these alternatives may just save you the expense of upgrading your whole motherboard or system .The thing that got me interested in this topic was a July 1990 Byte article reviewing two 25 Mhz 486 systems. The big news is that a 25 Mhz 486 CPU is no faster than a 33 Mhz 386 CPU. The only benefit that you get for spending thousands of extra dollars for the 486 system is that the 486's built-in floating point unit (FPU) is about twice as fast as the 33 Mhz 80387 (that you can add to your 386 system for about $550 to $600.)

If you are maxed out with your current combination you have several alternatives upgrading to a faster motherboard or even the 486 system. Now that I've told you what my thesis is, let me back up a bit and explain the basics. A "numeric co-processor" or "math chip" is an integrated circuit chip that you can plug into your motherboard. Its sole purpose is to speed up numeric calculations. This chip does calculations which would otherwise be done with software running on the CPU chip itself.

Numeric co-processors only benefit a small number of users because there are two conditions that must be met in order for these chips to make a difference. One is that a good portion of your computer time is spent doing mathematical calculations. The second is that the software doing these calculations must be smart enough to detect the presence of a co-processor and use it.

Computer Aided Design (CAD) programs such as AutoCad usually require a co-processor in order to get anywhere near acceptable response time. Lotus 1-2-3, QuickBasic, PageMaker and Ventura are other common programs that can take advantage of the co-processor. (Ventura and PageMaker only take advantage of it when printing graphics.) If you are running one of these programs, and you can ascertain that the program is "compute-bound" as opposed to "I/O-bound" (such determination is a whole science unto itself) then ask yourself if the computations are "number crunching" or "character crunching." If your application is compute-bound while doing mostly numeric calculations, then adding a numeric co-processor or upgrading to a faster alternative co-processor will allow your programs to run much faster. If you are compute- bound, but the application is just moving data around and not doing actual numeric calculations then a co-processor will NOT make it run faster.

One application where a co-processor is useless is a dedicated file-server. Although the 80486 CPU is now touted as "ideal" for file-servers, it is a waste of money for such an application. The extra money you spend for the 80486 is better spent on faster disk drives or more memory for buffers. File- servers don't use the floating point unit.

The claim to fame of the Intel 80486 CPU chip is that it has the numeric co-processor built-in. You don't need to add one. If you have an 8088, or an 80286 or an 80386, there is probably an empty chip socket on your computer's motherboard where you could plug in the co-processor. The part number of the co-processor depends on the part number of your CPU. The price depends on the speed (Mhz rating) and the chip maker.

MEMORY CARD

The 768 MB and 512 MB memory upgrades include OS patches and
the latest PDC firmware installation kit.Check the version of firmware on the system with the version in Table 1-2. If the system does not have the required firmware, update the firmware using the instructions provided with the installation kit.


The 8 GB (A3839A) memory upgrade includes the latest PDC firmware installation kit.
For HP-UX, the required OS patches are provided in product number B6191AA. This
product should have been ordered with the memory upgrade. MPE/iX requires Releases
6.0, Express 1, and 6.05 PDC to support 3.75 GB of memory; Releases 6.5 and 6.05 PDC
are required to support memory greater than 3.75 GB up to 16 GB.


Check the version of firmware on the system with the version in Table 1-3. If the system
does not have the required firmware, then update the firmware following the instructions
provided with the installation kit.


This section contains information on how to install DIMMs on the 8 GB memory board. If you are not installing an 8 GB Memory Board, go directly to the next section of this
manual, “Gaining Access to the Card Cage”. If the customer ordered an 8 GB Memory
Board, you will have to install DIMMs on a memory carrier board before installing the
board in the PMB card cage.


Each memory carrier board is divided into quadrants. Each quadrant comprises eight
DIMM sockets. Refer to Figure 1-1. Socket locations in each quadrant are numbered.
Socket location numbers for quadrants on the left side of the memory board are numbered
on the left side of each socket. Socket location numbers for quadrants on the right side of
the memory board are numbered on the right side of each socket.
DIMMs are installed in each quadrant according to the following rules:


DIMMs are installed on the carrier board in sets of four. Each DIMM in a set must be installed in a different quadrant. (After all of the DIMMs are installed, there should always be an equal number of DIMMs in each quadrant.). The first DIMM in a set can be installed in any unoccupied position in any quadrant.The initial location in which a DIMM is installed determines where the remaining three DIMMs in the set must be installed in the other three quadrants. For example, if you install a DIMM in location 1A, the remaining three DIMMs in the set must be installed in locations 1B, 1C, and 1D. Likewise, if you install the first DIMM in a set in location 7A, then the remaining three DIMMs must be installed in locat.

MICROCHIP

The biochip technology was originally developed in 1983 for monitoring fisheries, it’s use now includes, over 300 zoos, over 80 government agencies in at least 20 countries, pets (everything from lizards to dogs), electronic "branding" of horses, monitoring lab animals, fisheries, endangered wildlife, automobiles, garment tracking, hazardous waste, and according to the experts – humans (which we’ll examine in detail later). To date, over 7 million animals have been "chipped". The major biochip companies are A.V.I.D. (American Veterinary Identification Devices), Trovan Identification Systems, and Destron-Fearing Corporation.

The current, in use, biochip implant system is actually a fairly simple device. Today’s, biochip implant is basically a small (micro) computer chip, inserted under the skin, for identification purposes. The biochip implant system consists of two components; a transponder and a reader or scanner. The transponder is the actual biochip implant. The biochip system is a radio frequency identification (RFID) system, using low-frequency radio signals to communicate between the biochip and reader. The reading range or activation range, between reader and biochip is small, normally between 2 and 12 inches.

The transponder is the actual biochip implant. It is a passive transponder, meaning it contains no battery or energy of it's own. In comparison, an active transponder would provide it’s own energy source, normally a small battery. Because the passive biochip contains no battery, or nothing to wear out, it has a very long life, up to 99 years, and no maintenance. Being passive, it's inactive until the reader activates it by sending it a low-power electrical charge. The reader "reads" or "scans" the implanted biochip and receives back data (in this case an identification number) from the biochip. The communication between biochip and reader is via low-frequency radio waves.

The biochip-transponder consists of four parts; computer microchip, antenna coil, capacitor and the glass capsule. The microchip stores a unique identification number from 10 to 15 digits long. The storage capacity of the current microchips is limited, capable of storing only a single ID number. AVID (American Veterinary Identification Devices), claims their chips, using a nnn-nnn-nnn format, has the capability of over 70 trillion unique numbers. The unique ID number is "etched" or encoded via a laser onto the surface of the microchip before assembly. Once the number is encoded it is impossible to alter. The microchip also contains the electronic circuitry necessary to transmit the ID number to the "reader".

Antenna Coil is normally a simple, coil of copper wire around a ferrite or iron core. This tiny, primitive, radio antenna "receives and sends" signals from the reader or scanner.Tuning Capacitor The capacitor stores the small electrical charge (less than 1/1000 of a watt) sent by the reader or scanner, which activates the transponder. This "activation" allows the transponder to send back the ID number encoded in the computer chip. Because "radio waves" are utilized to communicate between the transponder and reader, the capacitor is "tuned" to the same frequency as the reader.

Glass Capsule "houses" the microchip, antenna coil and capacitor. It is a small capsule, the smallest measuring 11 mm in length and 2 mm in diameter, about the size of an uncooked grain of rice. The capsule is made of biocompatible material such as soda lime glass. After assembly, the capsule is hermetically (air-tight) sealed, so no bodily fluids can touch the electronics inside. Because the glass is very smooth and susceptible to movement, a material such as a polypropylene polymer sheath is attached to one end of the capsule. This sheath provides a compatible surface which the bodily tissue fibers bond or interconnect, resulting in a permanent placement of the biochip.

The biochip is inserted into the subject with a hypodermic syringe. Injection is safe and simple, comparable to common vaccines. Anesthesia is not required nor recommended. In dogs and cats, the biochip is usually injected behind the neck between the shoulder blades. Trovan, Ltd., markets an implant, featuring a patented "zip quill", which you simply press in, no syringe is needed. According to AVID "Once implanted, the identity tag is virtually impossible to retrieve. The number can never be altered."

The reader The reader consists of an "exciter" coil which creates an electromagnetic field that, via radio signals, provides the necessary energy (less than 1/1000 of a watt) to "excite" or "activate" the implanted biochip. The reader also carries a receiving coil that receives the transmitted code or ID number sent back from the "activated" implanted biochip. This all takes place very fast, in milliseconds. The reader also contains the software and components to decode the received code and display the result in an LCD display. The reader can include a RS-232 port to attach a computer.

The reader generates a low-power, electromagnetic field, in this case via radio signals, which "activates" the implanted biochip. This "activation" enables the biochip to send the ID code back to the reader via radio signals. The reader amplifies the received code, converts it to digital format, decodes and displays the ID number on the reader's LCD display. The reader must normally be between 2 and 12 inches near the biochip to communicate. The reader and biochip can communicate through most materials, except metal.

COMPUTERS

According to a 1999 survey by Healtheon Corp. (part of a three-year study of the computer needsand expectations of 10,000 physicians), regular online activity by physicians has increased 42 percent just in the last three months; 85 percent of the physician respondents said they used the Internet. Why the sudden increase? There are probably many reasons, but among them would appear to be the need for greater efficiency and a general rise in consumer online activity.
Physician use this era of declining reimbursements and thinning wallets, physicians are being asked to practice more efficiently, and the Internet can be a great help.


For example, the New York Board of Regents recently announced that New York doctors will be able to use e-mail (and faxes) to transmit prescription requests beginning this month. The Internet also has great promise as a tool for patient-records management, scheduling, patient education and claim submission, among other uses.

In another study of physician Internet use, FIND/SVP, a research and advisory service, reported that 65 percent of physicians think the Internet can enhance their access to clinical information and business news, although only 46 percent expect to find high-quality professional information online.

Despite some reservations about the quality of the content, many physicians have embraced this technology wholeheartedly. Thirty percent of the physicians surveyed by Healtheon already have web sites highlighting their practices, and 16 percent plan to develop them. Medical specialty organizations also are moving this direction: According to the Healtheon study, nearly a third of these groups have web sites.

Doctors also are increasing their use of e-mail. Sixty-three percent report using e-mail every day, says Healtheon, and 33 percent of respondents reported using e-mail to communicate with patients, a jump of 200 percent from the previous year.


Issues of security do linger. In the Healtheon survey, just over one third of the respondents indicated that security was a primary concern during e-mail and other Internet use. There is no federal legislation to protect health data privacy, and state laws offer uneven protection against inappropriate disclosure. Under the Health Insurance Portability and Accountability Act, Congress is given until August 1999 to enact privacy legislation.

DOLPHINS

One of man’s favorite animals is the dolphin. This sportive sea mammal has long enjoyed better press than, say, Fred Astaire. In France it was a symbol of royalty; Shakespeare uses it as a symbol of aquatic grace and beauty. Legends of its beneficence to shipwrecked sailors have circulated since ancient Greece.

Movies and documentaries portray dolphins as high-IQ and human-friendly critters, possibly communicating in their own special language. Dolphins have even been described as ”highly evolved spiritual beings.“ Environmentalists want to protect it against the tuna industry (though killing the poor tuna is okay).

But the dolphin’s lucky streak may be coming to an end. William J. Broad reports in the New York Times that the lovable dolphin has an ”unexplained darker side.“It seems there is credible testimony and evidence that dolphins have a mean streak. They kill porpoises and even dolphin calves; there are pathetic stories of dead porpoises and baby dolphins washing up on the coast of Virginia, their lifeless bodies bearing telltale teeth-marks and injuries. Untamed dolphins have been known to bite humans.

It has reached the point where the federal government has mounted a campaign to warn us against the dangers of wild dolphins. Such warnings are presumably authorized by the Interstate Commerce Clause, and next we can expect a federal campaign to observe young dolphins for the purpose of spotting the early warning signs.

Nobody can explain why dolphins display aggressive behavior, particularly against their own young; though there are mutterings about some ”evolutionary“ reason for it, it appears to be irrational, serving no survival purpose. Unlike most mammals, dolphins don’t eat what they kill (though they do eat squid and fish for nourishment). They seem to be driven by what Samuel Taylor Coleridge called ”motiveless malignity,“ battering smaller creatures, smashing their skulls and vertebrae, and biting them to death for the fun of it.

”Infanticide is common in nature,“ Mr. Broad notes. ”Females kill their young when food is scarce and male lions and bears, for example, sometimes kill the young of a female taken as a new mate, giving them a reproductive and evolutionary edge.“ Such animals must be pretty smart if they grasp the concept of evolution.

But of course the fact that other mammals kill their young doesn’t make it right for dolphins to do it. This is the old ”everybody does it“ excuse. ”Nature red in tooth and claw ...“”We have such a benign image of dolphins,“ says Dr. Dale J. Dunn, a veterinary pathologist. ”So finding evidence of violence is disturbing.“ Yes, and sad. All of us like to think of the dolphin as our friend; now we’re told that its smile is hypocritical, like that of the wretched crocodile or the president of the United States.

The dolphin has been taking us for a ride. But in fairness, we’ve wanted to be fooled. The benign animal, infused with evolutionary wisdom, has replaced the noble savage in the sentimental mythology that perennially asks why civilized human beings can’t just return to Nature. Illusions about Nature are of a piece with liberal illusions about human nature and the possibility of universal peace and brotherhood.For some animal lovers, man suffers by comparison with beasts. In the words of George Orwell’s Animal Farm: ”Four legs good, two legs bad.“ (Many would add: ”No legs best of all.“)

For thousands of years, Nature has been something human beings have yearned to get the hell out of. Illusions about Nature’s benignity arose only after the escape was complete, and people could visit a safely contained parcel of Nature — in the zoo, the park, or the aquarium — without being at her mercy. In confinement, dangerous beasts became harmless, observable, even lovable. Tenderness replaced terror.

Animal life does offer valuable intimations of human nature, but these aren’t entirely encouraging. Gorilla colonies, for instance, don’t roll out the red carpet for human visitors; it took Diane Fossey months to earn the grudging trust of the mighty apes she studied. The Ku Klux Klan would have shown more hospitality.Broadly speaking, animals are violent, predatory,
xenophobic, possessive, and lacking in compassion. We owe them no apologies. Besides, many of them taste good.