Table of Contents
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) datasheet
- Infrared distance sensor Sharp GP2Y0A21YK0F (measuring distance 10-80 cm) datasheet
- Light intensity sensor (photoresistor) VT935G (resistance 18,5 kΩ on 10 lux) datasheet
- temperature sensor (thermistor NTC) (resistance 10 kΩ on 25 °C) datasheet
- Potentiometer 5 kΩ
Electrical connections
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.
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.
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.
Connecting the Sensors module
