Tech Research project: Sonar sensor

Tech Research project

The Project:

For our tech research, we decided to work with the Devantech SRF04 Ranger .
This is a powerful, ultrasonic sensor that can detect objects from 3 cm to 10 feet away.

The SRF04 Ranger:

- Uses voltage of 5V
- Range = 3cm to 10 feet
- Weight : 0.4 oz
- Size : 1.75" w x 0.625" h x 0.5" d
- Frequency : 40 KHZ
- Beam pattern:

Connecting the sensor to the board:

The connections from the sensor to the board follow this diagram to the left. And here is how our wired board looks.

So we started by hooking up the sensor to the breadboard, and programmed the chip using this code. However, there was no response from the sensor.We tweaked the code endlessly, hoping to see some life in the numbers in our Serial window, but still nothing. After working several hours on this, we wrote to Tom & Michael for their inputs.

Based on their inputs, we used this code. And it worked like a charm!!

So it seems in our first code, we had to define our clock as 4, and change to portb, as against porta that we were using. As our porta was set to analog input, this may have been a problem.