====== Sensor module ======
(Version 5.1)

Sensor module includes the combined board of sensors, low-pass filter and external sensors.

Sensor module features

  * Electret microphone
  * 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 10 kΩ
  * Ultrasonic distance measure 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}}

{{:examples:sensor:sensor_board_v51.png?500}}

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

On-board sensors are connected as follows:

^on-board notation^external notation^on-board sensor^microcontroller port^
|MIC|AD0|Microphone|PF0|
|LDR|AD1|Light intensity sensor|PF1|
|NTC|AD2|Temperature sensor|PF2|
|POT|AD3|Potentiometer|PF3|

==== Sensors ====

Every sensor on the board is connected through the multiplexer, enabling to select between on-board sensor or external sensor which can be connected to the same port through the connectors. By default all on-board sensors are connected to the analogous inputs of the microcontroller (ADC0-ADC3). Multiplexer is controlled with the port PG0.

[{{:examples:sensor:multiplexer_sch_v51.png?200  |Schematics of multiplexer}}]

[{{:examples:sensor:sensors_sch_v51.png?580  |Schematics of sensor connections}}]

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

Low-pass filter can be composed between external 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:rc_sch_v51.png?580  |Schematics of external sensor connections and low-pass filter}}]

==== Digital I/O connector ====

In addition to the sensors and analog inputs, there is a connector for digital I/O on the board. The pins of the connector are directly connected to pins PE2-PE5 of the controller.

[{{:examples:sensor:dio_sch_v51.png  |The D_IO connector}}]