Ultra sonic sensor, direct in the USB/PC?

Forum 2005-2010 (read only) Hardware Interfacing
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I would like to work with a ultra sonic sensor, but (if possible) I would like to connect it directly to the usb. Is there any distance sensor that I can connect directly to the PC??

Thanks.

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The short answer is "no".I don't understand all the details, but if you have an Arduino board or similar, look for a surface-mounted chip on it (same side as the tracks). As I see it, this chip converts the Arduino protocols to the USB protocols, so you're going to need at least a similar chip, if not the Arduino itself. And you need to amplify the output from your sensor first. :stuck_out_tongue:

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This sensor Ultrasonic Range Finder - LV-MaxSonar-EZ1 - SEN-00639 - SparkFun Electronics has a serial output that you may be able to connect to a PC using a serial to USB adapter. I say 'may' because the board (and rs-232 line) is powered from 5 volts. This is less than the normal rs-232 spec but the manufactures claim that it can drive PC serial ports. Download the datasheet and see if this could meet your needs.

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Hi,

its not USB though, but the Ultrasonic sensors from Maxbotix contain a demo software which you can download and in the PDF it explains how to directly connect it to your serial port, only GND and TX.
I have tested that when I got my sensor and it worked!

would be interesting how it works, I thought the sensors serial is TTL :o

Dan

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Dan, the item linked in the post above yours is the Maxbotix sensor.

would be interesting how it works, I thought the sensors serial is TTL

The sensor inverts the logic levels so it will work if the RS-232 port can cope with a signal that only goes from 0 to 5 volts (rs-232 usually is at least plus/minus 5 volts)

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hi, yes, you must have posted while i was writing :wink:

I thougt 0volts doesnt mean anything to RS232 instead it is -3 (logic 1) to +3 (logic 0) Volts?! anyway, it worked for me...

Dan

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Many PC interfaces implement rs-232 in a way that interprets any level above a few volts as positive, anything less as if it was negative. In fact, I think the original freeduino RS-232 boards worked that way.

That's not the way its supposed to be done, but it's a cheap shortcut that was popular in the days before the wide availability of the max232 chip. Still used by some to save a buck or two.

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Thanks a lot for the replys!