1.1 Sys Architecture

1.1 Sys Architecture

1. Registers

   • MAR
     • Holds memory address about to be used by the CPU
   • MDR
     • Holds data or instructions that have been fetched from memory
   • Program Counter
     • Holds the memory address of the instruction for each cycle
   • Accumulator
     • Stores the results of the calculations done by the ALU

2. FDE cycle

   • Fetch
   • Decode
   • Execute.

3. Characteristics

   • Clock speed
     • Number of instructions that can be carried out in a second (Hz) - These days in Ghz (Billion)
   • Cache size
     • Refers to how many frequently used instructions can be stored in the cache on the CPU.
   • Number of cores
     • How many individual processors (cores) are on a chip. The more cores, the more instructions can be done simultaneously.

4. Embedded systems

   • A computer system built into another device (usually designed for a specific purpose)

5. Components

   • ALU
     • Performs logical operations (AND, OR, NOT), Shift operations and Arithmetic operations (+,-, *, / )
   • Control Unit (CU)
     • Controls activities in the CPU (Such as flow of data between CPU and other parts) and makes FDE cycle happen in correct order
   • Cache
     • Sits between the CPU and RAM. Very fast. Holds frequently used data so that the processor doesn't have to keep going back and forth to the RAM.

6. Purpose of the CPU

   • Central processing Unit - This processes all of the data and instructions that make a computer system work