Memory Devices

RD' and WR' are control lines which is responsible for the direction of data flow between Microprocessor and Memory Unit. If RD'=0 and WR'=1, the processor is reading data If RD'=1 and WR'=0, the processor is writing data

The control lines of the microprocessor is directly connected to the control input of the memory unit. If OE' = 0 then the output terminal of the Memory unit is enabled and data flows from Memory Unit to Microprocessor. If WR' = 0, the Memory Unit receives the data and store to the location pointed by the address lines.

Below are examples of Memory Units;

Static RAM (Random Access Memory)
DRAM (Dynamic Random Access Memory)
EEPROM (Electrically Eraseable / Programmable Read Only Memory
EPROM (Eraseable / Programmable Read Only Memory