Devantech SRF05 sonar.
The sonar can be connected to any I/O pin but requires a +5v regulated supply. On the Axon this means using an ADC pin. The device can be operated in two different modes. We use 'Mode 2' since that only requires a single pin to drive it - and so you must connect the 'Mode' pin on the board to the ground pin. The sonar can measure distances up to 430 cm. It may be defined using:
Devantech_SRF05 sensor = MAKE_Devantech_SRF05(F0);
Where F0 is changed to be the required ADC input pin.
The sensor should be initialised in appInitHardware using:-
The sensor can then be read using:-
and then the distance in cm will be in sensor.distance.cm
According to the datasheet you should not read the sensor within 50mS of taking the previous reading. Otherwise you will get ghost echoes from the previous reading. This library will automatically detect if that happens and, in the event, will return the previous reading.