According to statistics, China's single chip has reached 1-3 million units of capacity, and about 16% annual growth rate, but compared to the world market share in China is less than 1%. This shows that SCM applications in China has just started, there are broad prospects. SCM application training personnel, especially in the engineering and technical personnel in the popularization of knowledge of SCM has important practical significance.
Dazzling array of today's SCM vendor, product performance varies. Specific situation, we should choose what type it? First, we come to understand two concepts: focus on instruction set (CISC) and Reduced Instruction Set (RISC). CISC microcontroller with the structure of the data lines and command line time-multiplexing, the so-called Von. Neumann structure. It commands a rich, more powerful, but to take instructions and data can not be taken at the same time, the speed is limited and prices are high. RISC microcontroller with the structure of the data lines and command line of separation, the so-called Harvard architecture. This allows the instruction fetch and data can be obtained simultaneously, and the width of the data due to the general command line, more similar to CISC Microcontroller instruction more processing instructions contain information on the implementation of more efficient, speed is also faster. At the same time, this single chip single-instruction multiple-byte program memory space utilization greatly increased, to realizing ultra-small. There are CISC MCU structure Intel8051 series, Motorola and M68HC series, Atmel's AT89 series, Taiwan Winbond (Winbond) W78 series, the Netherlands Pilips the PCF80C51 series; is a RISC structure Microchip's PIC series, Zilog's Z86 Series , Atmel's AT90S series, Samsung's Series 4-bit microcontroller KS57C, Taiwan Elan's EM-78 series. In general, the control relationship than the simple small appliances, you can use RISC-based microcontroller; control relationship more complex situations, such as telecommunications products, industrial control systems should be used CISC microcontrollers. However, RISC microcontroller rapid improvement of relations between its leader in the control where no less complex.
According to the different ways of program memory, the microcontroller can be divided into EPROM, OTP (one-time programmable), QTP (mask) three. The beginning of a microcontroller are used ROMless type (chip-free ROM, need to chip with EPROM), the popularity of the microcontroller play a significant role, but the emphasis on widely used interface MCU can not even enter into a misunderstanding. If only emphasizes the application of single chip interfaces, external I / O and memory, will lose the characteristics of the microcontroller. Currently most of the microcontroller program memory within the body was placed, to the application brought great convenience. It is worth mentioning that in the past the price of OTP MCU QTP 3 times, and now has dropped to 1.5-1.2 times the OTP type used to avoid order cycle, the bulk of the trouble is desirable.
Second, PIC MCU What are the advantages?
Since I MCU PIC 95 years since exposure, has been keen on the development and application of such a single chip. Many of my friends asked me: PIC in the end What are the advantages? Maybe you'll have this question, so here I am talking about some of the views a little.
1) PIC biggest feature is not to engage in a simple function of accumulation, but from reality, attention to product performance and price ratio, by the development of a variety of models to meet the application requirements of different levels. In practical terms, the application of different features and resources on the MCU needs are different. For example, the ignition of a motorcycle requires a I / O low, RAM and program memory space for small, high reliability, small microcontroller, the use of a 40-pin microcontroller and powerful, is not that large investment, but also to use inconvenient. PIC series from low to high with dozens of models to meet various needs. Which, IC12C508 only 8 pin MCU, is the world's smallest single chip, the model has 512 bytes of ROM, 25 bytes of RAM, an 8-bit timer, an input line, 5 I / O lines, the market price of 3-6 yuan in RMB. Such a microcontroller such as the motorcycle ignition is undoubtedly very suitable for the application. According to statistics, China's single chip has reached 1-3 million units of capacity, and about 16% annual growth rate, but compared to the world market share in China is less than 1%. This shows that SCM applications in China has just started, there are broad prospects. SCM application training personnel, especially in the engineering and technical personnel in the popularization of knowledge of SCM has important practical significance.
Dazzling array of today's SCM vendor, product performance varies. Specific situation, we should choose what type it? First, we come to understand two concepts: focus on instruction set (CISC) and Reduced Instruction Set (RISC). CISC microcontroller with the structure of the data lines and command line time-multiplexing, the so-called Von. Neumann structure. It commands a rich, more powerful, but to take instructions and data can not be taken at the same time, the speed is limited and prices are high. RISC microcontroller with the structure of the data lines and command line of separation, the so-called Harvard architecture. This allows the instruction fetch and data can be obtained simultaneously, and the width of the data due to the general command line, more similar to CISC Microcontroller instruction more processing instructions contain information on the implementation of more efficient, speed is also faster. At the same time, this single chip single-instruction multiple-byte program memory space utilization greatly increased, to realizing ultra-small. There are CISC MCU structure Intel8051 series, Motorola and M68HC series, Atmel's AT89 series, Taiwan Winbond (Winbond) W78 series, the Netherlands Pilips the PCF80C51 series; is a RISC structure Microchip's PIC series, Zilog's Z86 Series , Atmel's AT90S series, Samsung's Series 4-bit microcontroller KS57C, Taiwan Elan's EM-78 series. In general, the control relationship than the simple small appliances, you can use RISC-based microcontroller; control relationship more complex situations, such as telecommunications products, industrial control systems should be used CISC microcontrollers. However, RISC microcontroller rapid improvement of relations between its leader in the control where no less complex.
According to the different ways of program memory, the microcontroller can be divided into EPROM, OTP (one-time programmable), QTP (mask) three. The beginning of a microcontroller are used ROMless type (chip-free ROM, need to chip with EPROM), the popularity of the microcontroller play a significant role, but the emphasis on widely used interface MCU can not even enter into a misunderstanding. If only emphasizes the application of single chip interfaces, external I / O and memory, will lose the characteristics of the microcontroller. Currently most of the microcontroller program memory within the body was placed, to the application brought great convenience. It is worth mentioning that in the past the price of OTP MCU QTP 3 times, and now has dropped to 1.5-1.2 times the OTP type used to avoid order cycle, the bulk of the trouble is desirable.
Second, PIC MCU What are the advantages?
Since I MCU PIC 95 years since exposure, has been keen on the development and application of such a single chip. Many of my friends asked me: PIC in the end What are the advantages? Maybe you'll have this question, so here I am talking about some of the views a little.
1) PIC biggest feature is not to engage in a simple function of accumulation, but from reality, attention to product performance and price ratio, by the development of a variety of models to meet the application requirements of different levels. In practical terms, the application of different features and resources on the MCU needs are different. For example, the ignition of a motorcycle requires a I / O low, RAM and program memory space for small, high reliability, small microcontroller, the use of a 40-pin microcontroller and powerful, is not that large investment, but also to use inconvenient. PIC series from low to high with dozens of models to meet various needs. Which, IC12C508 only 8 pin MCU, is the world's smallest single chip, the model has 512 bytes of ROM, 25 bytes of RAM, an 8-bit timer, an input line, 5 I / O lines, the market price of 3-6 yuan in RMB. Such a microcontroller such as the motorcycle ignition is undoubtedly very suitable for the application.
LCD TFT module, display terminal serial
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