Chapter 1 -assembler Data Representation

The byte is considered as the most important data structure used by the 80x86 microprocessor because it is the fundamental unit of storage in computer systems. The microprocessor operates on data in the form of bytes, which are 8-bit units of information. All other data types, such as integers, characters, and floating-point numbers, are represented and manipulated using bytes. Therefore, the byte is crucial for performing calculations, storing data, and executing instructions in the 80x86 microprocessor architecture.

The correct answer is Mechanical Wave, Electric Wave, Electronic Wave. These three waves represent different stages in the development of computer technology. The first wave refers to the use of mechanical devices such as punch cards and mechanical calculators. The second wave represents the shift towards electronic components like vacuum tubes and transistors. The third wave signifies the advent of integrated circuits and microprocessors, leading to the development of modern computers. These three waves highlight the progression and evolution of computer technology over time.

The left shift operation in a bit string moves each bit one position to the left. The low bit is replaced with a 0, and the carry out bit 7 is determined. This means that the leftmost bit is lost and a 0 is added at the rightmost position. Therefore, the given statement is true.

A bit is the smallest unit of data on a binary computer. It can represent a value of either 0 or 1, and is used to store and transmit information in binary form. A collection of bits is used to represent larger units of data, such as bytes, which are commonly used to measure the size of files and memory.

The explanation for the given correct answer is that the right shift operation indeed moves each bit in a bit string one position to the right. This means that the high bit, which is the leftmost bit, is replaced with a 0 and the carry out bit, which is the rightmost bit, is shifted out. Therefore, the statement is true.

The correct answer is a single bit. A bit is the smallest addressable datum on x86 processors. It represents a binary value of either 0 or 1 and is used to store and manipulate data at the most basic level in computer systems. In contrast, a byte is composed of 8 bits and a kilobyte (KByte) is equal to 1024 bytes. Therefore, the statement "All above are correct" is not accurate as a bit is the smallest unit of data on x86 processors.

The given options consist of pairs of words. "Quad Byte" is a pair of words that does not have any specific meaning or association. "Double Word," on the other hand, is a pair of words commonly used in computer architecture to refer to a data type that is twice the size of a word. Therefore, "Double Word" is the correct answer as it is a meaningful pair of words with a specific context.

The hexadecimal code (BCD) represents 16 different values. Hexadecimal is a base-16 number system, which means it uses 16 distinct symbols to represent numbers. These symbols include the digits 0-9 and the letters A-F. Each digit in a hexadecimal number represents a value from 0 to 15. Therefore, with 16 different symbols available, the hexadecimal code can represent 16 different values.

The given statement is false. Intel's x8086 is not the main processor that establishes the basic Instruction Set. The correct answer is not provided.

A group of 16 bits from 0 up to fifteen is considered as a word. In computer architecture, a word is the natural unit of data used by a particular computer architecture or operating system. It is typically the largest size of data that can be efficiently processed by the computer's hardware. In this case, 16 bits make up a word, which is the correct answer.

In a binary signed number, the most significant bit (H.O) determines whether the number is positive or negative. When the H.O is equal to 0, the number is considered positive. Conversely, when the H.O is equal to 1, the number is considered negative.

A collection of bits can be represented by nibbles, bytes, words, and double words. A nibble is a collection of 4 bits, a byte is a collection of 8 bits, a word is typically 2 bytes or 16 bits, and a double word is usually 4 bytes or 32 bits. Therefore, all of the options mentioned (nibbles, bytes, words, and double words) can be used to represent a collection of bits.

A byte can represent 256 numeric values in the range 0 to 255. However, when it comes to representing signed numbers, one bit is used to indicate the sign, leaving only 7 bits to represent the magnitude of the number. This means that the range for signed numbers is -128 to +127.

The given answer is correct because in binary representation, the bits 0 to 3 represent the lower order (L.O.) bits, while the bits 4 to 7 represent the higher order (H.O.) bits. Therefore, bit 0 to 3 compromise the L.O. and bits 4 to 7 form the H.O. nibble.

The given question is asking for the terms used to refer to the low order bit and the high order bit of a byte. The low order bit is also known as the least significant bit (L.O.), while the high order bit is referred to as the most significant bit (H.O.).