Bit, byte, font length, frequency, clock cycle, bandwidth

Bit: in a binary system, each 0 or 1 is a bit, which is the minimum unit of memory.

Word Length: in computer technology, the number of digits of the binary number that the CPU can process at a time in a unit of time (at the same time) is called the word length. Therefore, an 8-bit CPU can process 8-bit data. Similarly, a 32-bit CPU can process 32-bit binary data per unit time.

Bytes are the data volume units in the computer.
In a computer, data only uses 0 and 1. (here, only one data point is represented, not a number.) A 0 or 1 occupies a "bit ", in the system, eight digits are defined as one byte to indicate commonly used 256 letters, symbols, and control marks. One digit is used for data verification, and the other seven digits are used to record data.

The frequency is also called the clock frequency. The unit is MHz, which indicates the computing speed of the CPU. The CPU operating frequency (clock speed) consists of two parts: the outer frequency and the multiplier. The product of the two is the clock speed. The frequency doubling is called the frequency doubling coefficient. There is a ratio between the CPU clock speed and the external frequency, which is the multiplier coefficient. The multiplier value ranges from 1.5 to 23, and is measured at an interval of 0.5. The frequency is multiplied by the multiplier, so any increase can increase the CPU frequency. Because the frequency does not directly represent the computing speed, under certain circumstances, it is likely that the actual computing speed of the CPU with a higher frequency is low. Therefore, the clock speed is only one aspect of CPU performance, and does not represent the overall performance of the CPU.

Clock cycle: it is the amount of time. People define 10 nanoseconds (NS) as a clock cycle. The clock cycle indicates the highest frequency that the SDRAM can run. A smaller clock cycle means a higher operating frequency. For memory of the pc100 specification, the running clock cycle should be no higher than 10 nanoseconds. The Conversion Relationship Between the nanosecond and the operating frequency is: 1000/clock period = operating frequency. For example, the expression of the working frequency of a pc100 memory chip with a nominal value of 10 nanoseconds should be 1000/100 = 100 MHz, which indicates that the rated operating frequency of the memory chip is 100 MHz. At present, some memory of excellent quality on the market can usually work at a frequency higher than the rated frequency, which brings great convenience to some friends who like the Super frequency. For example, kingmax's pc100 memory uses an 8-nanosecond chip. Compared with its MHz frequency, there is still much room for increasing the frequency, many users can make them work at a 133mhz or even higher frequency. Whether it can be used frequently reflects the quality of the memory chip and PCB. However, it is still not enough to judge the memory speed based on the clock cycle. The access time and delay time of the memory CAS also determine the memory performance to a certain extent.

 

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The processor chip works at a specific clock frequency. The speed of the processor is measured by the clock frequency.

First, you need to understand what frequency is, the unit of frequency is Hz (HZ ). 1Hz is the completion of one cycle per second, and 10Hz is the completion of 10 cycles per second. However, the Unit of Hz is too small, and the signal frequency is usually expressed in kHz, MHz, or GHz.

1 GHz = 1000 MHz 1 MHz = 1000 kHz 1 kHz = 1000Hz

A period is the minimum time unit for the processor to process commands. Each computer command must be completed in several cycles.

The faster the clock frequency of the processor, the shorter the time it takes to complete an instruction, and the faster the speed, or the faster the processor can complete more instructions within the same period. If the clock frequency is 1 GHz, it means that 1000000000 cycles can be completed per second, and the execution of commands is faster than the 1 MHz processor.

The clock frequency is composed of the outer frequency and the frequency doubling. The clock frequency is equal to the outer frequency × the frequency doubling. Generally, the higher the clock speed, the more commands completed in a clock cycle, and the faster the CPU speed. However, since various CPUs have different internal structures, not all clock frequencies have the same CPU performance. The external frequency is the operating frequency of the system bus, while the frequency doubling refers to the multiple of the CPU external frequency and the frequency difference.