Found 409 Articles for Microcontroller

In this program we will see how to count number of odd numbers in a block of elements.Problem StatementWrite 8085 Assembly language program to count number of odd numbers in a block of data, where the block size is 10D. The block is starting from location 8000H.DiscussionThe Odd Even checking is very simple. we can determine one number is odd or even by checking only the LSb. When LSb is 1, the number is odd, otherwise it is even. In this program we are taking a number from memory and then ANDing 01H with it. if the result is nonzero, ... Read More

In this section we will count elements which are lesser than 0AH using 8085.problem StatementThere is an array of some elements. Write 8085 Assembly language program to count number of elements that are lesser than 0AH.DiscussionThe array is placed at location F051H onwards. The F050 is holding the size of the array. The logic is simple. At first we will take the array size into the B register. The C register will count number of elements less than 0AH. We will take numbers one by one from memory, then compare it with 0A. if the CY flag is set it ... Read More

Here we will see how to check whether two nibbles of a number are same or not.Problem StatementWrite 8085 Assembly language program to check whether upper nibble and lower nibbles are same or not.DiscussionTo check the nibbles, we have to mask at first. So we need to mask the lower nibble and upper nibble and store them into different registers. The upper nibble will be shifted to the right four bits to make it lower nibble. Then we can check both are same or not. If they are same store 00 at F150 location, otherwise store FF at F150 location.InputAddressDataF050FE AddressDataF050AA Flow ... Read More

Now let us see a program of Intel 8085 Microprocessor. In this program we will see how to generate pulse waveform.Problem Statement:Write 8085 Assembly language program to generate continuous square wave.DiscussionTo generate square wave with 8085, we will rotate 10101010 (AAH) continuously. We have to 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 be 1, thus the pulse will be generated.InputNo input is given in this caseFlow Diagram programAddressHEX CodesLabelsMnemonicsComments800016, AA MVI D, AAHLoad 10101010 into D80027AROTATEMOV A, DLoad D to A800307 RLCRotate A ... Read More

Now let us see a program of Intel 8085 Microprocessor. In this program we will see how to simulate the hexadecimal counter.Problem StatementWrite 8085 Assembly language program to simulate hexadecimal counter.DiscussionHexadecimal counters in 8085 is similar to the binary counter. There are two different parts. The main counting part and the delay part. We have to define a delay subroutine to generate delay between each number while counting. We are considering that we have some external display which are connected through IO port, that will display the result in hexadecimal form.InputHere we are not providing any input.Flow Diagram ProgramAddressHEX CodesLabelsMnemonicsCommentsF00006, FF MVI ... Read More

In this program we will see how to perform modulus of the first array corresponding to the next array.Problem StatementWrite 8086 Assembly language program perform modulus of the first array corresponding to the next array.DiscussionIn this example there are two different arrays. The arrays are stored at location 501 onwards and 601 onwards. The size of these two arrays are stored at offset location 500. We are taking the array size to initialize the counter, then by using loops we are getting the modulus of the elements one by oneInputAddressData……500045010F5020B5030550408……601046020A6030260403……Flow DiagramProgram    MOV SI, 500     ;Point Source index ... Read More

In this program we will see how to subtract the contents of two different arrays.Problem StatementWrite 8086 Assembly language program to subtract the contents to corresponding elements which are stored in two different arraysDiscussionIn this example there are two different arrays. The arrays are stored at location 501 onwards and 601 onwards. The size of these two arrays are stored at offset location 500. We are taking the array size to initialize the counter, then by using loops we are subtracting the elements one by oneInputAddressData……5000450109502035030850406……60104602016030260403……Flow DiagramProgram    MOV SI,  500     ;Point Source index to 500     MOV CL,  [SI]    ;Load the ... Read More

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