The microcontroller corresponds to the robot’s brain. It is he who will process the information coming from the sensors and which will give the desired response to the servomotors. The microcontroller is made up of four parts: A microprocessor which will take care of the information processing part and send orders. It is itself composed of an arithmetic logic unit (ALU) and a data bus. It is therefore he who will execute the program embedded in the microcontroller. A data memory (RAM or EEPROM) in which the temporary data necessary for the calculations will be stored. It is in fact the working memory which is therefore volatile. A programmable memory (ROM), which will contain the instructions of the program controlling the application to which the microcontroller is dedicated. This is a non-volatile memory since the program to be executed is a priori always the same. There are different types of programmable memories that will be used depending on the application. Especially :
- OTPROM: programmable only once but not very expensive.
- UVPROM: it can be refaced several times thanks to ultraviolet rays.
- EEPROM: it can be electrically refaced several times like flash memories. The last part corresponds to auxiliary resources. These are usually:
- Parallel and serial input / output ports.
- Timers to generate or measure signals with high temporal precision.
- A / D converters to process analog signals.
Below is the appearance of a microcontroller and the input / output diagram: