Input devices¶

This is a copy of the Guillem’s class notes. You can find the latest version here

Input devices #1 [Guillem]¶

Why we need sensors
Neurons, I/O and Bio indicators
Sensing the environment
Close loop systems
Inferring metrics
- Bike speed from counting wheel turns
- Water tank distance from distance from above
Composed sensors
- Radar: emitter (output) and receiver (input) working in sync
Complex post processing: Compur vision
- From a list of colors (pixel matrix) to meaningful data (i.e. object location based in color tracking)

The section is aimed at INPUTS (sensors) but many concepts work also for OUTPUTS (motors, LEDs)

How to choose sensor?
- Integrated circuits, breakout boards, and off-the-shelf devices
  - IC Component
  - Adafruit IMU Breakout
  - Wii Nunchuck (check in Wallapop, Cash converters, Ebay…)
How to wire a sensor?
- We will always look for well documented sensors learn.sparkfun.com, learn.adafruit.com
- Download the EAGLES from the Breakout boards to help you, example
- Electronic recipes
  - Voltage dividers
  - Pull up and pull down resistors
How to code for a sensor?
- Fab Academy sensors
- Sensor interfaces:
  - Is it on? DigitalRead
  - What’s the voltage? Analog to Digital Converter AnalogRead
  - How many times on? Pulses
  - Tell me soDigital Communication: Serial / UART, SPI, I2C :warning: We will always use an specific sensor library implementing the comunication

[Code Examples] https://github.com/fablabbcn/arduino-workshops/tree/master/Hello%2044

The ATtiny can do amazing things but will require us to optimize the code to an uncessary level when we just want a protoype…