Buffer: The buffer register is also called a buffer. It is divided into two types: input buffer and output buffer. The function of the former is to temporarily store the data sent by the peripheral so that the processor can take it away; the function of the latter is to temporarily store the data sent by the processor to the peripheral. With the numerical control buffer, the high-speed working CPU can coordinate and buffer the slow-working peripherals to realize data transmission synchronization. Since the buffer is connected to the data bus, it must have a three-state output function.
Line driver: Generally speaking, a computer has three buses: address, data, and control. Because there are many loads to be driven on the bus, the CPU is a large-scale integrated circuit and does not have the power driving capability. The function of the bus driver is to provide power driving. The second reason is Yes, the CPU bus is often a time-sharing multiplexed bus; that is, in different periods, the functions of the signals appearing on the pins are different. A latch is required to store and separate the signals, and the bus driver functions as a latch.