8086 Microprocessors & Peripherals

Static Memory Interfacing The general procedure of static memory interfacing with 8086 as follows: 1. Arrange the available memory chips so as to obtain 16-bit data bus width. The upper 8-bit bank is called ‘odd address memory bank’ and the lower 8-bit bank is called ‘even address memory bank’. 2. Connect available memory address lines […]
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INTERFACING ANALOG TO DIGITAL DATA CONVERTERS This topic is aimed at the study of 8-bit and 12-bit analog to digital converters and their interfacing with 8086. In most of the cases, the PIO 8255 is used for interfacing the analog to digital converters with a microprocessor. We have already studied 8255 interfacing with 8086 as […]
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6.1 8255 Programmable Peripheral Interface and Interfacing The 8255 is a widely used, programmable parallel I/O device. It can be programmed to transfer data under data under various conditions, from simple I/O to interrupt I/O. It is flexible, versatile and economical (when multiple I/O ports are required). It is an important general purpose I/O device […]
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Interfacing Devices Memory Devices and Interfacing Interfacing Devices Any application of a microprocessor based system requires the transfer of data between external circuitry to the microprocessor and microprocessor to the external circuitry. Most of the peripheral devices are designed and interfaced with a CPU either to enable it to communicate with the user or an […]
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DOS INTERRPUTS 5.1 Introduction The DOS (Disk Operating System) provides a large number of procedures to access devices, files and memory. These procedures can be called in any user program using software interrupts “INT n” instruction. The DOS interrupt INT 21H provides a large number of services. A function code has been allocated to each […]
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ASSUME CS: PROGRAM, DS: PROGRAM, SS: PROGRAM. LABEL: Label The Label directive is used to assign a name to the current content of the location counter. At the start of the assembly process, the assembler initialises a location counter to keep rack of memory locations assigned to the program. As the program assembly proceeds, the […]
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4.3.1 Interrupt Programming Program 4.3 Write a program to a create a file RESULT and store in it 500H bytes from the memory block starting at 1000:1000, if either an interrupt occurs at INTR pin with Type 0AH or an instruction equivalent to the above interrupt is executed. ASSUME CS:CODE, DS:DATA DATA SEGMENT FILENAME DB […]
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4.2.1 Programming for Stack Program 4.1 WAP to calculate squares of BCD numbers 0 to 9 and store them from 2000h offset onwards in the current data segment. The numbers and their squares are in the BCD format. Write a subroutine for the calculation of the square of a number. ASSUME CS:CODE,DS:DATA,SS:STACK DATA SEGMENT ORG […]
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4.1 LINKING AND RELOCATION Figure 4.1 Creation and execution of a program The DOS linking program links the different object modules of a source program and function library routines to generate an integrated executable code of the source program. The main input to the linker is the .OBJ file that contains the object modules of […]
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ASSEMBLER DIRECTIVES AND OPERATORS The main advantage of machine language programming is that the memory control is directly in the hands of the programmer, so that, he may be able to manage the memory of the system more efficiently. On the other hand, the disadvantages are more prominent. The programming, coding and resource management techniques […]
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