By Susan Wooldridge
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A set of articles taken from ''EDN'' electronics journal, designed to maintain working towards electronics engineers abreast of contemporary advancements within the fields of desktops, microcontrollers and different electronic undefined. The essays specialize in details pertinent to analog circuit layout
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They are encountered over and over again in the lists of papers published in those pioneering days, and it would be impossible to compile even a brief history of computers and software without mentioning them. But as they would be the first to point out, others not so well known today contributed just as much to the field. In more recent years, major developments have been announced not under the name of an individual but by large corporations, and even though the important concepts may be the work of only one or two, their names remain unknown.
24. Drum devices. edge of each disk so that the mechanism can sense the starting point for each track. 3. Transfer rate is the speed at which data can be read and loaded into memory, or taken from memory and written. This is in the order of 150,000 to 800,000 characters or bytes per second. Average access time is therefore the sum of average seek time, average latency, and transfer rate. The transfer rate is by far the smallest component, and is often disregarded in calculations. Facts and figures about three popular disk devices are given in Table 4.
They are: 1. Tape cannot be updated in situ. You cannot read and write on the same reel of tape at the same time. It is always necessary to have at least two tape drives and two reels of tape, one to be read from and the other to be written to. 2. Tape files must be processed serially. You cannot skip earlier records or blocks in order to get to ones that appear later on the tape. EVen if no processing is to be done to a block, it is still necessary to read it into memory and write it out to the new tape.