====== Sensors module v2.2 ======
(Version 2)

Sensors module includes the combined board of sensors, low-pass filter and separate distance sensors.

Sensors module features

  * Ultrasonic distance sensor Devantech SRF05 with cable (measuring distance 1-400 cm) {{:kit:datasheets:srf05tech.pdf|datasheet}}
  * Infrared distance sensor Sharp GP2Y0A21YK0F (measuring distance 10-80 cm) {{:kit:datasheets:sharp_gp2y0a21yk0f.pdf|datasheet}}
  * Light intensity sensor (photoresistor) VT935G (resistance 18,5 kΩ on 10 lux) {{:kit:datasheets:ldr.pdf|datasheet}}
  * temperature sensor (thermistor NTC) (resistance 10 kΩ on 25 °C) {{:kit:datasheets:ntc10k.pdf|datasheet}}
  * Potentiometer 5 kΩ

{{:examples:sensor:sensor_board.png?300|Sensors board}}

===== Electrical connections =====

[{{  :examples:sensor:sensor_schematics_portf.png?300|Controller module and Sensors module connection}}]

==== Sensors ====

Every sensor on the board is connected through the jumper, enabling to select between on-board sensor or external sensor which can be connected to the same port on the CON2 connector. By default all on-board sensors are connected to the analogous inputs of the microcontroller (ADC0-ADC3). In addition to on-board sensors, several analogous external sensors can be connected with sensor board through the connection CON2 to ports ADC4-ADC7. Attention have to be paid to the fact that the ATmega128 is using same ports (ADC4-ADC7) for JTAG programming. Both functions cannot be used simultaneously; the microcontroller can be configured to use just one. However if there is a need to use e the external sensors together with JTAG program, they can be connected to ports ADC0-ADC3, but appropriate jumpers have to be shifted.

[{{  :examples:sensor:sensor_schematics_sensor.png?400  |Schematics of sensors connections}}]

==== Low-pass filter ====

Low-pass filter can be composed between analogous inputs 0-3 (PF0-PF3). Resistor and capacitor will be connected to the socket for building up the low-pass filter. By default a low-pass filter is composed for the channel 0 (PF0). Resistor value is 10 kΩ and capacitor value is 100 nF.

[{{:examples:sensor:sensor_schematics_lowpass.png?580|Schematics of low-pass filter}}]

===== Connecting the module =====

While connecting the module it is suggested to follow the order as described below. Before connecting any cable make sure that the power is removed from Controller board.

  - Connect the Sensors module with Controller module by using the ribbon cable. NB! Check that the ribbon-cable is connected to the CON1/PF connector - not CON2
  - If needed connect the infrared distance sensor (black wire to GND)
  - If needed connect the Digital i/o module with LCD.
  - If needed connect the ultrasonic distance sensor with Digital i/o module (black wire to GND)
  - If needed connect the JTAG programmer with Controller module.
  - Connect the power supply with Controller module.

[{{:examples:sensor:sensor_connection.jpg?580|Connecting the Sensors module}}]