Troy: Thanks for the quick response. That's a great lead. I found I can get maybe 0.2 ms accuracy just using JavaScript. That translates to around 4cm, which isn't back.
When I have the time I'll see how much the PRU improves things. --Mark On Thursday, July 10, 2014 9:50:05 AM UTC-4, Troy Dack wrote: > > I came across this today > https://github.com/Teknoman117/beaglebot/tree/master/hcsr04-demo > > Might be just what you need. > > On Thursday, 10 July 2014 23:21:55 UTC+10, Mark A. Yoder wrote: >> >> I have a HC-SR04 Ultrasonic Ranging Module[1] I want to interface to the >> Bone. It outputs a pulse whose width is proportional to the distance to >> the object. >> >> The AM335x TRM says the eCAP Module (Enhanced Capture) can measure the >> time of a pulse. Has anyone written an eCAP kernel driver? Are there other >> ways to access the eCAP hardware? >> >> I'm running the 1-July-2014 Debian image. >> >> Thanks... >> >> --Mark >> >> [1] >> https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0CC4QFjAC&url=https%3A%2F%2Fdocs.google.com%2Fdocument%2Fd%2F1Y-yZnNhMYy7rwhAgyL_pfa39RsB-x2qR4vP8saG73rE%2Fedit&ei=cJG-U7ayGsyMyATGpoKIAQ&usg=AFQjCNEl7_92OTpEqYieKiT6D1fHJEwi9Q&sig2=aa8OnjEBQAGcLrjgDM4wSQ >> >> > -- 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/d/optout.
