primary memory
TRANSCRIPT
![Page 1: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/1.jpg)
PRESENTATION
Primary memory
![Page 2: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/2.jpg)
What is Primary memory ?
It is relatively a large memory . This memory is used for program and data storage during computer operation . Location in main memory can be accessed directly and rapidly by the CPU . The technology used for main memory is based on semiconductor technology .
![Page 3: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/3.jpg)
Types of primary memory
Read only memory (ROM) Programmable read only memory (PROM) Erasable programmable read only memory (EPROM) Electrically erasable programmable read only
memory (EEPROM) Random access memory (RAM)Cache memory
![Page 4: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/4.jpg)
Read only memory
ROM is used for storing programs and data permanently . The data and programs required for some applications are permanently store in the ROM chip . Thus a user may read a program or data from ROM but may not write on ROM .
![Page 5: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/5.jpg)
Programmable read only memory
PROMs are blank chip which have nothing recorded on them . Once instruction or data recorded into the chip by a special programming device . The PROM permanently stores the information like ROM .
![Page 6: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/6.jpg)
Erasable programmable read only memory
EPROM chip can be programmed as the PROM chip , but they can be erased and reprogrammed by a special programming device . The content of an EPROM chip can be erased by exposing it to ultraviolet light .
![Page 7: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/7.jpg)
Electrically erasable programmable read only memory
EEPROM is similar to EPROM expect that it is erased by applying electrical pulses to the chip . It is possible to reprogram an EEPROM chip via keyboard commands without removing the chip from the computer .
![Page 8: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/8.jpg)
Random access memory
RAM is temporary storage that can be read from or write into by the user . RAM is used primarily to store user programs and data . The content of RAM is generally volatile , and is lost when power is removed . When the system is powered up Programs and data to be used must be read into RAM through an input device .
![Page 9: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/9.jpg)
Types of RAM
Static RAM Dynamic RAM
![Page 10: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/10.jpg)
Static RAM
SRAM stands for static random access memory . it’s speed is high . It doesn’t require refreshing and generally used for cache . SRAMs control complexity is less , it is a costly instrument .
![Page 11: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/11.jpg)
Dynamic RAM
DRAM stands for dynamic random access memory . It is works slowly . It requires refreshing periodically and used for main memory . DRAMs control complexity is high , it’s cost is low .
![Page 12: Primary memory](https://reader036.vdocuments.mx/reader036/viewer/2022083105/587d62771a28ab32318b4bdd/html5/thumbnails/12.jpg)
Cache memory
As mentioned earlier the memory is slower then the CPU . System performance suffers when a fast device must wait to access data from a memory system . This may be an i/o device or cpu , and the memory system may be main memory or an external device . Because computer users always seem to want larger memories , computer designers must carefully decide memory cost and performance .