The main difference between CPLD and single-chip microcomputer is that

CPLD needs user programming to realize the desired processing function, while the function of single-chip microcomputer has been designed, and some or all of its functions are programmed by users themselves.

MCU is realized by software method, while CPLD is realized by hardware. CPLD can be regarded as a special decoding chip. Because it is implemented in hardware, its strength is fast. Just like watching a movie on a computer, you can decode it with CPU software, or you can decode it with graphics card hardware. Of course, hardware decoding is faster.

CPLD (complex programmable logic device) is a device developed from PAL and GAL devices, which belongs to the scope of large-scale integrated circuits. It is a digital integrated circuit that users can construct their own logic functions according to their needs. Its basic design method is to use the integrated development software platform, generate the target file with schematic diagram, hardware description language and other methods, and transmit the code to the target chip through download cable ("programming in system") to realize the designed digital system.

Microcontrollers is a kind of integrated circuit chip, which is a small and perfect device that integrates the functions of central processing unit (CPU), random access memory (RAM), read-only memory (ROM), various I/O ports, interrupt system, timer/counter, etc. (possibly including display drive circuit, pulse width modulation circuit, analog multiplexer, A/D converter, etc.) on a silicon chip by using VLSI technology.