ARM is a 32-bit RISC processor architecture developed by the ARM corporation. The business model behind ARM is based on licensing the ARM architecture to companies that want to manufacture ARM-based CPU’s or system-on-a-chip products.
The two main types of licenses are the Implementation license and the Architecture license.
- The Implementation license provides complete information required to design and manufacture integrated circuits containing an ARM processor core.
- The architecture license enables the licensee to develop their own processors compliant with the ARM ISA.
There are many features, that makes ARM the most popular architecture.
ARM cores are very simple compared to most other general purpose processors, which means that they can be manufactured using a comparatively small number of transistors, leaving plenty of space on the chip for application-specific macro-cells. This reduces the area taken by the die of embedded processor. For a single-chip solution, the smaller the area used by the embedded processor, the more available space for specialized peripherals. This in turn reduces the cost of the design and manufacturing since fewer discrete chips are required for the end product. ARM chip can contain several peripheral controllers, a digital signal processor, and some amount of on-chip memory, along with an ARM core.
For a portable Embedded System power consumption is the most critical issue. The ARM processor is specifically designed to be small for reduced power consumption. ARM ISA and pipeline design are aimed at minimizing energy consumption.
Hardware debug technology within the processor, enables run time debugging while executing the code. This reduce the time to market and development cost.