by Dinesh Thakur Category: DIGITAL CONCEPTS

8088

The 8088 is the chip that launched the PC revolution-IBM designed the original IBMPC around the 8088 microprocessor. The 8088 was also used in the PC/XT. Even by the standards of its day, the 8088 was slow, and it suffered from technical shortcomings that have bedeviled PC software developers ever since.



 
by Dinesh Thakur Category: DIGITAL CONCEPTS

Practically speaking, the 80486's main advantage over the 80386 is just that the 486 is faster. Even if you compare the two chips running at the same clock speed, the 486 will generally finish its calculations sooner, sometimes much sooner, than the 386.

 
by Dinesh Thakur Category: DIGITAL CONCEPTS

The 80386 chip has one big advantage over the 80286: it includes fully functional, built-in circuits for multi-tasking, or running two or more programs at the same time. Although software like Windows, DesQview, or Unix will let you "multi-task" using lowlier chips, the 80386 does it more reliably and with less hassle. Windows, for example, running in "386 Enhanced Mode," lets you use multiple standard DOS programs at the same time, whereas you're limited to only one DOS program at a time with an 80286. Another improvement in the 80386 is its ability to access even larger amounts of memory than the 80286, and to do so with less trouble. Again, DOS is oblivious to the extra memory, but you can buy software that bypasses this limitation through a DOS extender.

 
by Dinesh Thakur Category: DIGITAL CONCEPTS

The 80286 was the microprocessor used in IBM'SPC/AT. The 80286 calculates faster than the 8088. It also corrected one of the biggest problems with the 8088-its inability to access more than a small amount(1 megabyte) of memory. But-and this is a big catch-DOS couldn't takeadvantage of the extra memory. Why, you ask? Well, because DOS had torun on 8088-based computers too, so it couldn't be changed to accommodatethe new chip. Windows, however, does utilize the special talents ofthe 80286 in "standard mode." In fact, you can't run Windows 3.1 unlessyour PC has an 80286 or an even newer microprocessor. However, there isa way to create software that uses the extra memory but still manages torun in DOS.



 
by Dinesh Thakur Category: DIGITAL CONCEPTS

In digital circuit, a signal is represented in discrete states or logic levels. Digital signals are non-continuous and change in individual steps. They consist of pulses with discrete levels. The value of each pulse is constant but there is an abrupt change from one digit to next.

 
by Dinesh Thakur Category: DIGITAL CONCEPTS

Most of the people are familiar with ordinary electrical circuits where voltages and currents can be measured with dial-type meters or analog meters as they are technically called. Such meters follow changes in voltage (or current) in a smooth stepless manner. This is what analog really means in electronics: signals or physical quantities which can vary in smooth-changing, a stepless manner.

 
by Dinesh Thakur Category: BINARY CODE

Earlier computers were used only for the purpose of calculations i.e. they were only used as a calculating device. But now computers are not just used for numeric representations, they are also used to represent information such as names, addresses, item descriptions etc. Such information is represented using letters and symbols. Computer is a digital system and can only deal with l's and 0’s. So to deal with letters and symbols they use alphanumeric codes.



 
by Dinesh Thakur Category: BINARY CODE

The Gray code was designed by Frank Gray at Bell Labs in 1953. It belongs to a class of codes called the minimum change code. The successive coded characters never differ in more than one-bit. Owing to this feature, the maximum error that can creep into a system using the binary gray code to encode data is much less than the worst -case error encountered in case of straight binary encoding.

 
by Dinesh Thakur Category: BINARY CODE

Excess-3, also called XS3, is a non-weighted code used to express decimal number-s. It is another important binary code. It is particularly significant for arithmetic operations as it overcomes the shortcomings encountered while using the 8421 BCD code to add two decimal digits whose sum exceeds 9. This code is used in some old computers.

 
by Dinesh Thakur Category: BINARY CODE

The binary coded decimal (BCD) is a type of binary code used to represent a given decimal number in an equivalent binary form. Its main advantage is that it allows easy conversion to decimal digits for printing or display and faster calculations.

 
by Dinesh Thakur Category: BINARY CODE

Digital data is represented, stored and transmitted as groups of binary digits also known as binary code. The binary codes can be classified as shown in Fig.



 

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About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.