The memory and input/output

6.4 The Memory The main or external memory (or simply the memory) stores both instructions and data. For 8-bit microprocessors, the memory is divided into a number of 8-bit units called "memory words." An 8-bit unit of data is termed a "byte." Therefore, for an 8-bit microprocessor, "memory word" and "memory byte" mean the same […]
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8087 Numeric Data Processor

8087 Numeric Data Processor 1. Draw the pin connection diagram of 8087. Ans. The pin diagram of 8087 is shown in Fig. 19b.1. 2. What are the characteristics of 8087 NDP? Ans. The following are the characteristic features of 8087 NDP: z It can add arithmetic, trigonometric, exponential and logarithmic instructions to the 8086 instruction […]
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8086 Interrupts

8086 Interrupts 1. How many interrupts can be implemented using 8086 µP? Ans. A total of 256 interrupts can be implemented using 8086 µP. 2. Mention and tabulate the different types of interrupts that 8086 can implement. Ans. 8086 µP can implement seven different types of interrupts. z NMI and INTR are external interrupts implemented […]
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Input/Output Interface of 8086

Input/Output Interface of 8086 1. What are the two schemes employed for I/O addressing. Ans. The two schemes employed for I/O addressing are Isolated I/O and Memory I/O. 2. Compare Isolated I/O and Memory mapped I/O. Ans. The comparison is shown in Table 17.1 Table 17.1: Comparison between isolated and memory mapped I/O Isolated I/O […]
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Modular Program Development and Assembler Directives

Modular Program Development and Assembler Directives 1. What is modular programming? Ans. Instead of writing a large program in a single unit, it is better to write small programs— which are parts of the large program. Such small programs are called program modules or simply modules. Each such module can be separately written, tested and […]
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