MEMORY INTERFACING WITH 8085
The memory is made up of semiconductor material used to store the programs and data. Three types of memory is,
- Process memory
- Primary or main memory
- Secondary memory
TYPICAL EPROM AND STATIC RAM:
- A typical semiconductor memory IC will have n address pins, m data pins (or output pins).
- Having two power supply pins (one for connecting required supply voltage (V and the other for connecting ground).
- The control signals needed for static RAM are chip select (chip enable), read control (output enable) and write control (write enable).
- The control signals needed for read operation in EPROM are chip select (chip enable) and read control (output enable).
DECODER:
It is used to select the memory chip of processor during the execution of a program. No of IC's used for decoder is,
Table - Number of Address Pins and Data Pins in Memory ICs
Fig - Block diagram and Truth table of 2-4 decoder
Fig - Block diagram and Truth table of 3-8 decoder
