The embedded processor is the core of the embedded system and the hardware unit that controls and assists the system to run. According to its present situation, embedded processor can be divided into embedded microprocessor, embedded microcontroller, embedded DSP processor and embedded system on chip.
Embedded microprocessors
Embedded microprocessor is a processor with more than 32 bits and has higher performance. Different from the computer, only the functional hardware closely related to the embedded application is retained in the actual embedded application. Compared with the industrial control computer, the embedded microprocessor has the advantages of small size, light weight, low cost and high reliability, but the circuit board must include ROM, RAM, bus interface, various peripherals and other components, thus reducing the reliability of the system, technical confidentiality is poor. Embedded microprocessor and its memory, BUS, peripherals are installed on a circuit board, called a single board computer, such as STD-bus, PC104, etc. In recent years, some German and Japanese companies have developed “matchbox” type business card size embedded computer series OEM products. At present, embedded microprocessors mainly include AM186/88, 386EX, SC400, Power PC, 68000, MIPS, ARM series, etc.
2. Embedded DSP processor
The system structure and instruction of DSP processor are specially designed to make it suitable for executing DSP algorithm, with higher compilation efficiency and instruction execution speed. In digital filtering, FFT, spectrum analysis and other aspects, DSP algorithms are entering the embedded field. The application of DSP is transitioning from common instruction to embedded DSP processor. The embedded DSP processor has two development sources: first, DSP processor becomes embedded DSP processor after monolithic, EMC transformation, adding peripherals on chip, TMS320C2000/C5000 of TI company belongs to this category; The second is to add I)SP coprocessor in general microcontroller or SoC, such as Intel McS-296 and Siemens TriCore. Another factor promoting the development of embedded DSP processor is the intelligence of embedded system, such as various consumer products with intelligent logic, biological information recognition terminal, keyboard with encryption and decryption algorithm, ADSL access, real-time voice decompression system, virtual reality display, etc. This kind of intelligent algorithm generally has a large amount of computation, especially vector operation, pointer linear addressing and so on, and these are the advantages of DSP processor.
Embedded microcontroller
The typical representative of embedded microcontroller is single chip microcomputer. The embedded microcontroller generally takes a certain microprocessor core as the core, and integrates Flash, RAM, EEPROM, bus, bus logic, timer/counter serial port and other necessary functional modules inside the chip. In order to adapt to different application requirements, generally a series of single chip microcomputer has a variety of derivative products, each derivative product processor core is the same, the difference is the configuration and packaging of memory and peripherals. This can make the microcontroller and application requirements to the maximum, the function is not much, so as to reduce power consumption and cost. Compared with embedded microprocessors, the biggest characteristic of microcontroller is monolithic – greatly reduced in size, thus reducing power consumption and cost, and improving reliability. Microcontroller is the mainstream of embedded system industry at present. Microcontroller peripherals on the chip resources are generally rich, suitable for control, so called microcontroller.
Embedded system-on-chip (SOC) is a product that combines many functional modules to put the entire system on a chip. Socs are classified into general purpose and special purpose. General including M-core, some ARM series devices. Specialized soCs are typically dedicated to a system or class of systems and are not known to the average user.
These are embedded processors. And the embedded processor is divided into four categories, each category has different functions and uses, to understand thoroughly, to master the embedded processor.