The relationship between the CPU and the chip in ARM

ARM processor: The first low-power cost RISC microprocessor designed by Acorn**** in the UK. The Advanced RISC processor itself is a 32-bit design, but it also comes with a 16-bit instruction set, which typically delivers up to 35% savings over the equivalent 32-bit** while retaining all the benefits of a 32-bit system.

Cortex Architecture: ARM's products after the classic processor ARM11 have been renamed Cortex and are divided into three categories: A, R, and M, designed to serve a variety of different markets.

Differences between ARM cores and Cortex architectures:

1. The structure is different

ARM cores: The RM processor itself is a 32-bit design, but it also comes with a 16-bit instruction set.

Cortex Architecture: It belongs to the ARMv7 architecture, which is the latest instruction set architecture of ARM until 2010.

2. The application field is different

ARM kernel: Approximately 20% of the instructions in the CISC instruction set are reused, accounting for 80% of the entire program**. The rest of the instructions are not used very often, accounting for only 20% of the programming.

Cortex Architecture: The technology used in the Cortex processor series based on the V7 architecture is also different depending on the application field, which is called the Cortex-A series based on V7A, Cortex-R series based on V7R, and Cortex-M series based on V7M.

The traditional naming of ARM processors is ARM + number: ARM7, ARM9, ARM11, and after ARM11, ARM has used a new naming method: Cortex, which should be ARM12 compared to the traditional way.

The Cortex architecture is currently divided into 3 series, with performance and complexity from low to high: M, R, and A.

The main target of the Cortex-M series is the microcontroller market, which is the traditional MCU, microcontroller, etc., which is divided into several grades, such as Cortex-M0, Cortex-M0+, Cortex-M1, Cortex-M3, and Cortex-M4.

The Cortex-R series is primarily targeted at high-end real-time systems, including baseband, automotive, mass storage, industrial and medical markets, and is available in the Cortex-R4, Cortex-R5, and Cortex-R7 grades.

Targeted at the general processing application market, the Cortex-A series offers a full range of ultra-low-cost handsets, smartphones, mobile computing platforms, digital TVs, and set-top boxes to enterprise networking, printers, and server solutions for devices hosting rich OS platforms and user applications, with processors including: Cortex-A5, Cortex-A7, Cortex-A8, Cortex-A9, Cortex-A12, Cortex-A15, Cortex-A17, Cortex-53, Cortex-A57, and many more.

1. The ARM architecture is like the overall design of building a house, it is the big framework of the chip, it is a chip design scheme (architecture), and it is a public technical solution, anyone can make a chip according to this scheme, but if the purpose of making a chip is to turn it into a commodity, it must be authorized by ARM. At present, all chip manufacturers in the world are designed and manufactured according to this scheme, and all software vendors also design software according to this standard, so the compatibility of products is not a problem.

2. Since its official establishment in 1990, ARM has made continuous breakthroughs in the field of 32-bit RISC (Reduced Instruction Set Computer CPU) development, and its structure has developed from V3 to V7. Since its establishment, ARM has been providing IP (intelligence property) to major semiconductor manufacturers for intellectual property rights, and has never been involved in the production and sales of chips, coupled with the design of the core has the advantages of low power consumption, low cost and other significant advantages, so it has won the strong support of many semiconductor manufacturers and machine manufacturers, and has achieved great success in the field of 32-bit embedded applications, accounting for 75% above the 32-bit RISC embedded products market. It has established a market leadership position in low-power, low-cost embedded applications.

There are more than 50 large international companies that design and produce ARM chips, and domestic companies such as ZTE Chain Lead Communications, Wushu and Huawei Communications have also purchased ARM core cores for the design of communication chips.

The purpose of this blog is to sort out some concepts about ARM and ARM chips, such as what S3C2440 is, and what is its relationship with ARM.

ARM mainly designs the ARM series AISC processor cores, which do not produce chips, but only provide IP cores. Let's start with an example to explain the architecture, cores, processors, and chips: the S3C2440, which is an SoC chip.

Note that it is not a CPU, 2440 is a bit similar to the 51 microcontroller we are familiar with, both belong to the embedded. The development of embedded has gone through three stages, namely SCM, MCU, SCM or MCU, and 2440 belongs to SOC. Below is the internal structure of 2440.

The arm920t in the middle is the 2440 processor, and the processor and core are a concept here in my opinion, but one is a hard concept and the other is a soft concept. The 920T here is both a processor and a core. And what Samsung does is something other than this CPU.

That is to say, Arm gave Samsung ARM920T, and Samsung designed the S3C2440 chip based on this processor.

Now let's talk about the ARM architecture, the architecture is actually a design idea, based on which the ARM company has designed different processors, please see this table below.

So we can see that the architecture of S3C2440 is armv4.

For example, the S3C2440 is based on the ARM920T core.

To sum up: a single rack-acre base corresponds to multiple cores, and a single core corresponds to multiple chips, and Arm provides cores to chip manufacturers, such as Samsung.