Found 558 Articles for Microprocessor

In this section we will see the basic comparisons between I/O port chips and the memory chips in 8085 microprocessor.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 ... Read More

Now let us see a program of Intel 8085 Microprocessor. In this program we will see how to alternate the D0 bit and send as output.Problem StatementWrite 8085 Assembly language program to alternate D0 bit. And send this as output.DiscussionAlternating D0 bit and sending as output is like generating the square wave. We are adding extra delay in each phase. To generate square wave with 8085, we will rotate 10101010 (AAH) continuously, and send D0 as output. We will mask the accumulator content by 01H. If this is 0, then output will be 0, if it is 1, output will ... Read More

Here we will see we can take all numbers which are in range 3CH and 64H from an array using 8085.Problem StatementWrite 8085 program to take all numbers which are greater or equal to 3CH, and lesser than 64H from an array. Numbers are stored at 8001 onwards, 8000 is holding the size of array, the results will be stored from 9000.DiscussionTo solve this problem, we will take the numbers from memory. Then compare it with 3C. If the Carry flag is set, then it indicates that the number is less than 3C, so just skip it. otherwise compare it ... Read More

Here we will see how we can take all numbers whose D7 and D1 bits are 0, using 8085.Problem StatementWrite 8085 program to take all numbers from an array whose D7 and D1 bits are 0. Numbers are stored from 8001, and the array size is stored at 8000. Store the result from 9000 onwards.DiscussionTo solve this problem, we will AND the number by 82H (1000 0010). If the result is 0, then the number is acceptable. If the bit position D7 and D1 are 0, then only the result will be 0.InputAddressData……80000A8001E98002D38003618004AD80052A80061F80075D8008A68009A9800A35…… Flow Diagram ProgramAddressHEX CodesLabelsMnemonicsCommentsF00021, 00, 80 LXI H, 8000Load the ... Read More

Here we will see how we can subtract two consecutive elements in an array using 8085.Problem StatementWrite 8085 program to subtract two consecutive elements of an array and store them in the same location. The results will be placed at the same location from where they are taken. The numbers are stored from location 8001. The size of array is stored at 8000.DiscussionHere we will solve this problem by using one subroutine. That will subtract two consecutive numbers and stored them into correct position. That subroutine will be called multiple times to subtract all consecutive pairs. The task will be ... Read More

Here we will see how we can add two consecutive elements in an array using 8085.Problem StatementWrite 8085 program to add two consecutive elements of an array and store them in the same location. The carry will be placed at bottom of the other byte. The numbers are stored from location 8001. The size of array is stored at 8000.DiscussionHere we will solve this problem by using one subroutine. That will add two consecutive numbers and stored them into correct position. That subroutine will be called multiple times to add all consecutive pairs. The task will be followed half of ... Read More

Here we will see we can take all numbers which are not 00H from an array using 8085.Problem StatementWrite 8085 program to take all numbers which are not 00H from array, and store them into different location. Numbers are stored at 8001 onwards, 8000 is holding the size of array, the results will be stored from 9000.DiscussionTo solve this problem, we are taking the number from memory, then perform OR operation on the number and 00H. If the zero flag is enabled, then we can understand that the number was 00, so we just ignore that. Otherwise we just store ... Read More

Here we will see we can take 16-bit BCD data from memory and unpack it, then store into memory using 8085.Problem StatementWrite 8085 program to take 16-bit BCD number from memory then store each digit by unpacking into different locations.DiscussionTo solve this problem, we will create one subroutine, that can unpack 1-byte BCD number and store into memory, then we will use that subroutine for two times to store 16-bit data. The subroutine will cut the numbers by masking upper nibble and lower nibble, and store into memory.Input1234 in the DE register pairFlow Diagram ProgramAddressHEX CodesLabelsMnemonicsCommentsF00031, 00, FC LXI SP, FC00Initialize stack ... Read More

Here we will see how we transfer a block of data in reverse order using 8085.Problem StatementWrite 8085 program to transfer a block of N-bytes in reverse order. The block is stored at location 8001 onwards, the size of the block is stored at 8000. The block will be moved at location 9000 onwards.DiscussionTo solve this problem, we are taking the size of the block at first. The DE register pair is set to point at destination address 9000H. The HL pair is set to point to the last element of the block. If the block size is 0A, then ... Read More

Here we will see how we can implement running light with some delays using 8085.Problem StatementWrite 8085 program to implement running light display with appropriate delays using lookup table stored from memory location 8100H on words.DiscussionThe patterns are stored at location 8100 onwards. We are using 8255 port IC to display the content in LED displays. After displaying, it calls the delay to wait for some time and call the next byte from memory to display. So the display pattern will be like below - ProgramAddressHEX CodesLabelsMnemonicsComments800031, 00, 82START:LXI SP, 8200 HInitializing the SP80030E, 15 MVI C, 14 HInitializing the counter800521, 00, ... Read More