Lesson 4

Lesson 4

1. Microcontroller

   • What is a microcontroller?
     • Is a computing device capable of executing a program and is often referred to as the “brain” or “control center” in a robot since it is usually responsible for all computations, decision making, and communications.
   • What can a microcontroller do?
     • -Program a repeating sequence where the microcontrollers turns a pin HIGH, waits for a moment, turns it LOW, waits for another moment and starts again. -Control other electrical devices such as actuators, storage devices, WiFi or Bluetooth interfaces, etc
   • What are the more specialized features in a microcontroller?
     • -can do more than the usual digital I/O, basic computations, basic mathematics, and decision taking. -integrate a voltage regulator in their development boards
   • Analogue or Digital?
     • Digital: A digital signal is used in order to assess the binary state of a switch. A momentary switch or push button closes a circuit when pressed, and allows current to flow . A digital pin connected to this circuit would return either LOW or 0 or a HIGH .
     • Analogue: A variable resistor or potentiometer is used to provide an analogue electrical signal proportional to a rotation. As illustrated below, when a potentiometer is connected to a 5V supply and the shaft is turned, the output will vary between 0 and 5V, proportionally to the angle of rotation. The ADC on a microcontroller interprets the voltage and converts it to a numeric value. Therefore if you suspect the device you plan to connect will provide a value that is proportional to something else, it will likely need an analogue pin.
   • What about programming?
     • microcontrollers can be programmed in various high-level languages including C, C++, C#, Processing (a variation of C++), Java, Python, .Net, and Basic. Of course, it is always possible to program them in Assembler but this privilege is reserved for more advanced users with very special requirements
   • Why not use a standard computer?
     • Because the standard computer is used in more complex sistems and is also more expensive.
   • Choosing the right Microcontroller
     • -Which microcontroller is the most popular for my application? -Does it have any special features the robot requires?..... -Are the accessories I need available for a particular microcontroller?
   • What does the future hold?
     • The single-board computers are essentially computers you may have used about 5 years ago, and incorporate many devices into one board. They can run a complete operating system and can connect to external devices such as USB peripherals, LCDs etc. Unlike their ancestors, these single-board computers tend to be much more power efficient.