Memory interfacing in 8085 microprocessor pdf

#Memory interfacing in 8085 microprocessor pdf serial
#Memory interfacing in 8085 microprocessor pdf code

Port A and B can be programmed as either input or output (all eight line must be same), while port C is split into two 4 bit halves (Port C upper (PC4-PC7) and Port C lower (PC0-PC3)) that can be separately programmed as input or output. It contains three independent 8 bit ports named Port A, B and C. The 8255 Programmable Peripheral Interface (PPI) is a general purpose interface device which is widely used in microprocessor design. Programmable Peripheral Interface (PPI) 8255 and Universal Synchronous Asynchronous Transmitter and Receiver (USART) 8251 is an input and output device for the Development System to communicate with the outside world. AddressДata Register USART 8251 Control/Status Register USART 8251 Port A 8255 Port B 8255 Port C 8255 Control Port 8255 NOT USED Figure 2 shows the I/O map for the 8085 Development System. Both devices have a unique address where it is decoded as isolated I/O. The Development Board is provided with two input and output devices Programmable Peripheral Interface (PPI) 8255 and Universal Synchronous Asynchronous Transmitter and Receiver (USART) 8251. User can changed the setting to other memory address by configuring the jumper (J16) on the board. Whilst the memory space 2000H - 3FFFH is allocated for RAM which is used for user program, data and stack (Default Setting).

#Memory interfacing in 8085 microprocessor pdf code

The first 8K of memory space 0000H - 1FFFH is allocated for EPROM which contains the monitor program code for the system. 1.1.1ДЇigure 1 shows the memory map for the Development System. The Development System can address up to 64K of memory devices and 255 addresses for I/O devices. This Development System has two different address maps Memory Map and I/O Map. Overall system operation is controlled by the monitor program which resides in the EPROM.

#Memory interfacing in 8085 microprocessor pdf serial

The board is connected to the computer through its serial port. The circuit diagram for this system is as Appendix 1. The basic components of the 8085 Microprocessor Development System board consist of ДЁ085 8-bit Intel Microprocessor 8K Byte memory EPROM - 2764 8K Byte memory RAM - 6264 I/O Device - 8255 Serial Communication (UART) вЂ“ 8251 Monitor Program In case if you are using RAM then you have to connect one more pin for writing operation.LABORATORY 1 INTRODUCTION TO 8085 MICROPROCESSOR DEVELOPMENT SYSTEM BOARD 1. There is not the facility for writing data. and D0 to D7 of the 8085 microprocessor will be connected to the data bus of the memory.ДЄs we know that the it is EPROM, so only RD pin is connected to the microprocessor. In this system A0 to A11В lines of MicroprocessorВ will be connected to theВ address linesВ of the memory.

So 12 lines will be used for interfacing. Interfacing a ROMВ memory of 4096*8 with 8085 Microprocessor:. Then the size of the memory will be M Г— N. For example, If a particular memory chip is capable of storing M words with each word having N-bits. Memory Size:-The number of location and number of bits per word will vary from memory to memory. Memory:-A memory is a digital IC which stores the data in binary form. Generally, RAM or ROM is used for memory interfacing. Now a days Semiconductor memories are used for storing purpose. Memory Interfacing:-As we know thatВ any system which process digital data needs theВ facility for storingВ the data.В Interfacing is a technique to be used for connecting the Microprocessor to Memory.