In this tutorial, we are going to learn about Memory
Memory – It is the mind through which data or information is encoded, stored, and retrieved if needed and also It is the retention of information over time for the purpose of influencing next action.
Register Memory: It is to number of general purpose registers present within a processor.
More the no of general purpose registers within a processor more is the speed.
Cache Memory: Instructions and data which are presently wed are stored in this memory.
Primary or Main memory: We have of two types the primary memory.
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RAM ROM
RAM: Random access Memory-
It is also known as red/write memory, temporary memory or volatile memory. It words only when the supply is present .
RAM
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SRAM DRAM
SRAM: Static RAM
- Data is stored as voltage
- Flip- Flop are used to store other data
- 1 Memory call may contain 3-4 transistors.
DRAM: Data is stored as charge b/w data – substrate of a Mas – transistor.
As the charge leaves of fervently it must be refreshed fervently .
Density is more in DRAM.
ROM: ROM, PROM, EPROM, EEPROM.
Read only memory (ROM)→Memory calls are designed as arrays having metallic fuses.
Is pure is there →1
Is pus is not there →0
Programmable Read only memory (PROM):
The pusses are replaced by Diodes or transistor such that memory is programs but not many time only one time)
Erasable Programmable Rom: Chip will be having a slaws window, when exposed to UV light the data is erased.
It will have very long time for erasing the data (up to /30sec)
Glass window.
Electrical erasable Programmable Rom:
It is also known as non volatile RAM
Electrical voltage is used to erase the data, by using a logic programmer.
DBADVANTGE:
Data erasing time is more It depends on the type of IIC mostly (15-25 sec)