1.2 Memory V.3

1.2 Memory V.3

1. Solid State

   • Storage media with no moving parts or a device that uses flash memory

2. ROM(Read-only memory)

   • ROM is non-volatile memory when the computer turns off as it is permanently on the computer on the ROM chip and holds the system start up

3. Virtual Memory

   • It is simulated memory that is written memory to a file on a hard drive
     • Disk Thrashing
       • The process of moving applications ,files between cache ,ram and virtual memory
     • applications on the computer (ram cannot support more memory to be used than there is in the system
   • This is needed to run programs as sometimes the RAM cannot support it and is more memory to be used

4. RAM(Random access memory)

   • RAM is volatile memory when computer switched off it losses all data .Programs and data in use are stored inside of RAM

5. Register

   • This is a component for holding short term memory , used to store addresses or data currently being worked on
     • Examples of registers are MAR(Memory Address Register),MDR(Memory Data Register) ,Cir (Current Instruction Register)
       • MAR is used to store the address of the next instruction /data to be accessed
       • MDR is used to store the data to be brought form / sent to main memory Program Counter ,used to store the address of the next instructions
       • CIR (Current instruction Register) This holds the current instruction to be executed, having been fetched from memory.

6. Flash Memory

   • Flash memory is solid state memory
     • Solid State Media
       • A physical device outside he computer that that can save storage
   • Can be used to transfer data and can save storage
   • It is very portable which means it can be taken to many places but it is easy to loss as it is usually small.Flash memory sometime can be very expensive

7. Cache

   • Cache is a hardware or software component that stores data to make the CPU execute the instructions and data faster

8. Power On self-Test (POST)

   • Bios chip performs checks .
   • Components are present and functioning correctly
   • Checks completed CPU starts operating system