Gustavo, I posted a link to my blog below. I experienced this problem a couple years ago when I first started with MaxBotix sonars. The datasheet isn't 100% clear, but the serial signal is inverted. That is what the person in the RPi forum meant about the meaning of the 1s and 0s. You cannot simply flip the received data because the whole stream is inverted (to include start bits, etc.). You need to invert everything. In my post you will find a simple circuit made of 2 resistors and a transistor that will invert the signal for you. If you prefer, you can purchase a hex inverter to accomplish the same thing.
I hope it helps you. To save you from finding my other posts, here is the link http://blog.lemoneerlabs.com/post/Hearing-aids On Monday, November 4, 2013 11:57:41 AM UTC-6, Gustavo Oliveira wrote: > > Hello, > I'm trying to read from a LV-Maxsonar-EZ0 using the serial interface. > > I have connected the wires correctly and I have placed an overlay in uart2. > The problem is the data I'm reading from the sensor. I can only get > garbage, but its not completely wrong because the data changes according to > the distance to obstacle. > > The datasheet for the sensor can be found here: > datasheet<http://www.maxbotix.com/documents/MB1000_Datasheet.pdf> > . > > I searched google for a day and couldn't find anything... > Someone posted in a raspberry pi forum that the problem is the meaning of > 1s and 0s, but I changed active_low to 1 and I got the same. > > I'm not very proficient with electronics, so I might take some time > following instructions. > Nonetheless all the help will be welcome. > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
