Embedded systems are not just complex projects in electronic laboratories–they are present in everyday devices. Every mobile device, electric toy or kitchen appliance has some electronic board which usually includes a programmable device–microcontroller. This is a special microprocessor with peripheral devices and I/O ports. Depending on the volume of the device the manufacturer can decide whether to develop an ASIC–a dedicated integrated circuit which performs all functions for this device or to make a standard board with discrete components. In both cases some microcontroller is used, either as a soft core in ASIC or a standard integrated circuit.
There is a plethora of choices from open-source projects to various IP cores with significant royalties for each device. Despite this choice there are few microcontroller families that are popular because of their flexibility, powerful development tools or because of historical reasons.
This is currently the hottest RISC core used in almost all mobile phones, portable devices and many other applications. It has powerful instruction set, low consumption, offers easy integration and there are many good development tools for easy development and debugging. The ARM core is also used in many popular microcontroller families from Atmel, Luminary Micro (now Texas Instruments), NXP and many other manufacturers. These microcontrollers are very popular among embedded engineers and are used in various applications from automotive industry to hobby projects.
This is one of the most popular microcontroller families from Atmel. It is also very popular among hobby engineers and it is used in many projects from simple LED controllers to complex communication devices. The RISC architecture offers fast execution and low power consumption. Development tools are available for free which is a great bonus for electronics enthusiasts. AVR is a direct competitor to Microchip’s PIC. Some favor AVR, others like AVR. There is no clear winner. Both families work well. It is up to the developer/programmer what he like or prefers.
This is a leading microcontroller family from Microchip. PICs are available in very small packages with only few pins and also as powerful 32-bit microcontrollers with many peripheral modules and I/O pins. They are very popular among hobby engineers–in hobby projects you will find either AVR or PIC.
This is a very old 8-bit microcontroller architecture that has managed to survive for more than 30 years. Many excellent compilers, a lot of code examples and simple development has contributed to the popularity of this family. This core is still used in many modern microcontrollers from Silabs, NXP, Atmel and many other microcontroller manufacturers. It is very likely that the 8051 is the most widely used core in embedded applications. Of course, many new designs will probably use ARM or some other advanced architecture, but because of popularity of the 8051 family in the past and availability of development tools it is still used in many applications.