Found 475 Articles for 8085

Before having a discussion regarding the merits of I/O mapped I/O and demerits of memorymapped I/O, let us have a generic discussion regarding the difference between I/O mapped I/O and memory mapped I/O.In Memory Mapped Input Output −We allocate a memory address to an Input Output device.Any instructions related to memory can be accessed by this Input Output device.The Input Output device data are also given to the Arithmetic Logical Unit.Input Output Mapped Input Output −We give an Input Output address to an Input Output device.Only IN and OUT instructions are accessed by such devices.The ALU operations are not directly ... Read More

Information is also stored in an Input Output port chip similar to a memory chip. Information of 1 byte are stored in an Input Output port chip on the other hand information of few bytes are stored in the Input Output port chips. An example to be cited as only 1 byte of information is stored in Intel 8212 I/O port chip, but 3 bytes of information are stored in Intel 8255 chip. Moreover, a large number of memory locations like 1K, 4K, 8K etc. are contained in the memory chips. We select memory chip location by the address pins ... Read More

There are two types of Input Output ports. They are Programmable Input Output ports and Non-Programmable Input Output ports. Since the functions of Programmable Input Output ports changed by software they became more popular. We don’t need to change the wiring rather the hardware of the I/O port to change the function. Intel 8255 is a popular Input Output chip based on port. Whereas the I/O ports which are non-programmable needs to change the wiring or the hardware to change its complete function. We will see in later that the connection needs to be changed when 8212 works like an ... Read More

Let us consider ALS-NIFC-01, which is a stepper motor interface. Using 26-core flat cable, it is connected to ALS kit. It will be used for interfacing two stepper motors. In our current experiment, we use only one stepper motor. The motor has a step size of 1.8°. The stepper motor works on a power supply of +12V. Power supply of +5V (white wire), GND (black), and +12V (red) is provided to the interface. Note that -12V supply is not used by the interface. We shall have to make sure that the +12V supply has adequate current rating to drive the ... Read More

We write an 8085 assembly language program for the generation of triangular waveform using the Digital to Analog Converter (DAC) interface. The display of the waveform is seen on the CRO.Let us consider a problem solution in this domain. The problem states that: To get unipolar output, J1 is shorted to J2 on the interface. To display the waveform on a CRO, connect pin 1 of connector P1 to CRO signal pin, and pin 2 of connector P1 to CRO ground pin.Program; FILE NAME DAC_TO_TRIANG.ASM ORG C100H X DW 00FFH ; the fall of rise and time I proportional directly to ... Read More

We write a program for the generation of rectangular interface of Digital to Analog Converter (DAC) interference: Let us consider a problem solution in this domain. The problem states that: To get unipolar output, J1 is shorted to J2 on the interface. To display the waveform on a CRO connect pin 1 of connector P1 to CRO signal pin, and pin 2 of connector P1 to CRO ground pin.The program is stated as below.; FILE NAME DAC_TO_RECT.ASM ORG C100H X DW 00FFH ; ‘OFF’ time is proportional to this value Y DW 00C0H ; ‘ON’ time is proportional to this value ... Read More

The Model ALS-NIFC-07 which on approximating successfully ADC is clearly described in this topic. It consists of a programmable timer interface which connects to the kit of ALS-SDA-85M by using a flat cable of 26 crores. The connector C1 gets connected to the interface by the Input Output connector P3 in the kit for the ALS, which is implemented on a flat cable. The power supply of +12V, -12V, +5V, and GND gets connected to the interface. The circuit description is shown below –C1 is connected to connector P3 (or P4) on ALS kit, for ADC interface purposeC2 is connected ... Read More

We shall write a program in assembly language just for the simulation of a multiplexer 8 to 1 which is used by the logic controller interface.The pins of the 8 to 1 multiplexer to be simulated are assumed to be as shown in the fig.For this multiplexer simulation, 8255 ports as indicated in the following provide the inputs and outputs.Port B used as I7-0 inputs;Pin 7 of Port C used as chip select;Pins 6-4 of Port C used as select inputs;Pin 0 of Port A used as output of multiplexer.Sample CodeFILE NAME Prog_MUX.ASM ORG C100H TABLE DB 01H, 02H, 04H, 08H, ... Read More

Moreover, we write an assembly program in 8085 assembly language just to simulate a 4-bit ALU by using an interface which is based on the logic controller. The Arithmetic Logical Unit always performs an addition, subtraction, AND operation, or OR operation, which is based on the 4-bit inputs for the desired operations to be performed.For the simulation of the Arithmetic Logical Unit all the terminal inputs and outputs are provided by the ports of 8255 as it is indicated in the figure below.The Pins ranging from 7-4 in the Port B are used as the inputs of X3-0;The pins ranging ... Read More

We write a program in 8085 in the assembly language just for the evaluation of only wo Boolean expressions of 4 variables by using the interface of logic controller. The output of the program should be logically tested automatically by the output by the input changing from the inputs from 0000, 0001, … to 1111 just to press any key.Let us say we want to evaluate the following Boolean expressions.First of all, truth table for the Boolean expressions is written down as shown in the following table.PQRSXY000010000100001010001100010010010100011010011100100001100101101010101100110000110111111000111100The inputs of the PQRS gets connected to PB3, PB2, PB1, and PB0 of ... Read More