Compilation of notes _ Basics

1 bus

• Internal bus: realize the link between the devices within the CPU (computing, controller, registers, etc.).
• Bus line (external bus): links to achieve the CPU and other devices on the motherboard.
  • Address bus
    • CPU memory cell specified by the address bus.
    • N has a CPU address lines, the width of the address bus of the CPU is N, the CPU may look for a maximum of N th power of 2 memory cell (byte).
  • Control bus
    • Control bus of the CPU determines control external devices.
    • How many root control of the bus, it means how many CPU provides control of external devices.
  • Data Bus
    • Data between the CPU and memory or other delivery device.
    • It determines the width of the data bus data transfer speed of the CPU and the outside world. N number of data buses, a N-bit binary data can be transmitted (i.e., the N bit).

2 memory

• Random access memory (RAM): readable and writable, power loss of data.
• A read only memory (ROM): read-only, power data is not lost.

3 memory address space

• Various types of CPU memory are seen as a logical memory, the memory on each physical space occupied logical address period, CPU can manipulate the segment, it is the physical storage operation.