SP-40-38F Ultrasonic Sensor Board CuteDigi/SolidDigi

Greetings All,

I recently picked up a couple of $10 SP-40-38F Ultrasonic Sensor Boards. The didn't include any directions and CuteDigi's site only includes C code and assembly, but no arduino code or a general data sheet.

The pins are labelled as: Pin 1:GND Pin 2:OUTPUT LOW pulse Pin 3:Input 40khz pulse Pin 4:+5v

The product is listed here: http://www.cutedigi.com/product_info.php?products_id=4282

The only other information I was able to find is this: http://soliddigi.com/news/shownews.php?lang=en&id=32

I tried hacking at some code for other ultrasonic sensors to no avail.

Thanks in advance...

  1. You need to drive the "Input 40KHz pulse" with a burst of 40KHz square wave. I think you can probably do this by reprogramming counter/timer 2 to increase the pwm frequency to 40KHz, so that you get the 40KHz from one of the PWM pins.

Generating a 40KHz burst in software (by toggling an output pin at 40KHz) might also be possible, but getting the frequency exactly right would be tricky.

  1. You need to connect "output pulse low" to an Arduino digital input. My interpretaion of the data is that you will read LOW on this pin when a reflected 40KHz signal is detected by the receiver.

Thanks so much for the response. I have been quite unsuccessful with this sensor and have instead picked up a PING sensor, which has worked out perfectly.