על ידי tal4 » ש' דצמבר 02, 2006 10:47 pm
באנגלית אבל גם טוב...
The sonar sensor is composed internally of two parts. One part is fed into a digital
out port with a local ground on the Handy Board. This part actually sends out the high-frequency sounds which are expected to bounce off a remote object. The other is the receiver side. This receives the reflected sounds and interprets them internally. The sonar then sends back a pulse modulated signal to the Handy Board into one of its digital input ports. This receiver side is also fed a +5V power connection from the Handy Board. It is rather ironic that the receiver gets the power while the transmitter gets the ground. Since both the ground and power sides are needed, the decision was most likely arbitrary. In either case, the sonar was treated as a blackbox unit for our purposes. We were only concerned with its predefined interface.