What is the difference between a register and a latch?

Difference Between Latch and Register:

1.The registers are synchronous clock control, while the latches are potentiometric signal control. Latches are generally controlled by level signals and are level-sensitive. Registers are generally controlled by clock signals and are edge-sensitive.

2.The output of the register usually does not change with the change of the input terminal, and only when the clock is active, the data of the input end is sent to the output terminal (into the register), and the output terminal of the latch usually changes with the change of the input terminal, and only when the latch signal arrives, the state of the output terminal is latched, so that it no longer changes with the change of the input terminal.

Register. In actual digital systems, synchronous timing logic circuits that can be used to store a set of binary ** are usually called registers Because the flip-flop has a memory function, it is convenient to use the flip-flop to form registers. Since a flip-flop can store one bit of binary code, connecting the clock ports of n flip-flops can form a register that stores n-bit binary code.

latch. A sequential logic circuit consisting of several clock-controlled D flip-flops that can store multi-bit binary ** at a time. The data is valid later than the clock signal.

This means that the clock signal comes first, and the data signal comes later. In some combinator circuits, latches are sometimes used as data registers.

RAM is memory outside the CPU, registers are inside the CPU, used to save intermediate results, reduce the frequent exchange of data between the CPU and memory, thereby improving the speed of the system; The shift register has the function of a register and has a shift function; The latch and buffer are set to solve the speed mismatch between the two parts in the data transfer process.

Take a look at the chapters on flip-flops, registers, and latches in this book, and you might find something to gain. I was going to continue with you yesterday, but you're all mine.

Register. The differences with the scratchpad are: different operations, different classifications, and different mode state families.

First, the operation is different.

1. Register: The register is used to temporarily store instructions, data and addresses, and is a high-speed storage component with limited storage capacity.

2. Scratchpad: The scratchpad is used to temporarily store the bus that is closed by the data.

or an operand from a generic register and treat it as another operand.

Second, the classification is different.

1. Registers: Registers are divided into general registers, special registers and control registers.

2. Register: Scratchpad is divided into instruction scratchpad (IR) and program counter.

PC) and an accumulator (ACC).

Third, the way is different.

1. Register: The register adopts serial mode, and several clock pulses are used to complete the input or output operation, and the working speed is slow, but only one input or output data line is needed, and the transmission line is few, which is suitable for long-distance transmission.

2. Register: The scratchpad adopts a parallel mode, and only one Shishan Clock pulse can complete the data operation, and the working speed is fast, but it requires N input and output data lines.