Microcontrollers A microcontroller is a small computer which interacts with its environment, e.g switches, sensors, lights, motors...... It does not have its own operating system There is no keyboard, mouse, sound, video or internet connection It's program needs to be stored in an EPROM Once programmed it simply needs power to operate A low clock speed is common. This uses less power.

In PIC you choose your chip Factors to consider Clock frequency Size of program memory Erasable memory or not Number of digital IN and OUT pins Is analogue to digital included Cost

Introduction to the Arduino Comparison with the PIC microcontroller The Arduino is a hobby-type prototyping microcontroller It can take power from a USB socket or a battery or other source It uses an Open Source language called “Processing” akin to C++ It uses the PC as its programmer problema arduo = difficult problem; ino = small so arduino means no problem (my interpretation)

Introduction to the Arduino Comparison with the RPi The Arduino is a similar size and runs off 5V to 9V It can handle analogue signals as well as digital Many freely downloadable projects, both software and hardware (Open Source Hardware) A community of people well versed in prototyping Working projects may be purchased and fitted as a “shield”

Cost The Arduino Uno alone costs £17 Look in Maplins to see some of the shields which are available PIC stuff is available there too

Lamp example. What the program does. Fetches information from a web site From this it calculates a colour in hexadecimal and displays it Splits the hexadecimal into three to send intensity values to the 3 LEDs Displays the intensity of the light from the Arduino

Lamp example. What the Arduino board does. A momentarily ON switch, latches the three LEDs either permanently ON or OFF Adjusts their individual brightnesses according to information received from the program A photo diode measures light intensity and sends this to the program