Program to Read from external memory 8051 Expriments by Ravinder Nath Rajotiya - June 3, 2021May 9, 20220 Objectives: To learn interfacing of external memory with 8051 To understand the instructions for accessing the memory To develop a program to read and write data to external memory Theory: 8051 Microcontroller on the other hand has onchip 4KB of ROM and 128B of RAM. 8052 has 8KB of program memory (ROM) and 256 bytes of data memory (RAM). For simple to less complex applications this is sufficent, but, If the program and data tend to be larger and require more memory than available on 8051/8052 then external RAM and ROM can be interfaced with 8051 microcontroller. Thus, there is a provision of connecting both external RAM and ROM i.e., Data Memory and Program. Interfacing memory with 8051 We can interface a maximum of
Experiment-5 Reading a number from One Port and Sending it to another Port 8086 Programming by Ravinder Nath Rajotiya - April 15, 2021May 9, 20220 Aim: Write a Program to read 16 bit Data from a port and display the same in another port. Objectives: [ To learn configuring of Key board and display module with 8086 microprocessor using 8255PPI Design algorithm and develop a program for accepting data from oneport and displaying it to LCD connected to other port. Equipment Require: 8255 Display Module, 8086 trainer Kit Theory: A Simple approach We can make use of the 8086 IN and OUT instruction to read the data from the device attached to a port and send the data to another port. We can access the ports using direct addressing or indirect addressing Direct address can be provided in the instruction Indirect address is loaded in DX register. here is simple program statements for the
Programming Model 8085 8085 Microprocessor by Ravinder Nath Rajotiya - December 14, 2020May 10, 20210 Programming Model of 8085: The programming model of 8085 consist of an 8-bit accumulator, one flag register, 6 general 8-bit purpose registers, and two 16-bit special purpose registers. These registers are critically required when programming a 8085 processor. The different register in the programming model are explained below: Figure-1: Programming Model of 8085: Accumulator: Accumulator is an 8-bit register. For processing the numbers, 8085 assumes that one of the numbers is in accumulator. After processing, the result is accumulated in accumulator. The usage of the accumulator is given below in assembly language format: MOV A, M ; this instruction moves the content of a memory location into accumulator MOV B, C ; It moves the content of register C into register B ADD B ; it add
8255 PPI(Programmable Peripheral Interface) Microprocessor and Interfacing by Ravinder Nath Rajotiya - March 26, 2020April 21, 20220 8255 Programmable Peripheral Interface 8255 is a programmable peripheral interface IC which is used as an interface between the external device and the microprocessor for parallel communication. This IC is a 40-pi IC having three ports known as Port-A(PA), Port-B(PB) and Port-C(PC). these ports can operate in various modes. the complete details is given in the following PPTSs. Features of the 8255: It provide three I/O ports All the three I/O ports are latched Port operation is configurable by programming 8255 i.e. writing a control word in CWR BSR- bit set-reset mode allows individual pins of port C to be controlled to be set or reset. PIN diagram of 8255 8255 PPI is a 40-pin IC, it has three 8-bit ports named PA, PB