From owner-freebsd-arm@FreeBSD.ORG Fri Aug 22 03:43:48 2014 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 349D7756 for ; Fri, 22 Aug 2014 03:43:48 +0000 (UTC) Received: from mail-wi0-x236.google.com (mail-wi0-x236.google.com [IPv6:2a00:1450:400c:c05::236]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AEE503D90 for ; Fri, 22 Aug 2014 03:43:47 +0000 (UTC) Received: by mail-wi0-f182.google.com with SMTP id d1so9331916wiv.3 for ; Thu, 21 Aug 2014 20:43:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=CfDVLrJsCnEFtjpUd6GZyh4aaCuL95hIDk+LcS0sr20=; b=SsUaOTXFHeHqYybAlysqAP3NB95DmiedCUdNT/2RAoeTWq9YRT41HBMENgcAizQE+F sqavw7EAm0pmU7I37NjUKxZvvi1aXQ5jXjVgtr5SJORV2aP27fXFs6zn0ZHC2/lNBY3O UdSu9vsI3LAMTNieJSt6L9WKcQphBp4jWvLDD4kbfKRihKCVGydov+Z7Hh3zjeWmag59 SAPL4cC+BIoOsnq0g3UDCocntsBR7MoT3y/tmKZU5xOYi/hlNfjFetDpz/leIuM5abeB 22cmRd+eBCXNkX13x5xEv+azFiss4r/HvqIFp/Vj0FxK9HjBEgKK/lldxUvNLfjqRxCe rAVw== MIME-Version: 1.0 X-Received: by 10.180.35.134 with SMTP id h6mr8381495wij.0.1408679025717; Thu, 21 Aug 2014 20:43:45 -0700 (PDT) Received: by 10.217.125.66 with HTTP; Thu, 21 Aug 2014 20:43:45 -0700 (PDT) In-Reply-To: References: <5D802942-2D0F-4324-8212-C2871EEB6327@FreeBSD.org> <01562FB1-32C6-45AF-AB77-5BB80526E18C@FreeBSD.org> Date: Fri, 22 Aug 2014 00:43:45 -0300 Message-ID: Subject: Re: HC-SR04 and FreeBSD From: Evandro Nunes To: Rui Paulo , freebsd-arm@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Aug 2014 03:43:48 -0000 On Thu, Aug 21, 2014 at 4:13 PM, Rui Paulo wrote: > You can use an led instead of a multimeter. The point I'm trying to make > is to make sure the gpio number really corresponds to that port number. > still no success, but just an update... ok I added two led: pin 02: 0 gpio_2 ===> echo (orange LED) pin 03: 0 gpio_3 ===> trigger (blue LED) pin 49: 0 gpio_49 ===> previous echo and I have the two simple loops below. when I run loop1, BLUE LED blinks every second; when I run loop2 while loop1 stills run, ORANGE LED won't blink, and loop2 value still shows 0 value if I "gpioctl -c 2 OUT ; gpioctl -t 2", ORANGE LED will light, confirming LED is OK; thoses leds will light with 2-5v input... however I have no idea if the sonar output will range 2-5 or if it will be below 2 (i tried adding my hand very close and far away from the sensor but led was never lit) so I'd better use a multimeter for sure... loop1: while true ; do gpioctl -t 3; sleep .200; gpioctl -t 3 #gpioctl 3 sleep 1 done loop2: while true ; do gpioctl 2 sleep .500 done > > -- > Rui Paulo > > On 21 Aug 2014, at 11:44, Evandro Nunes wrote: > > On Thu, Aug 21, 2014 at 1:24 PM, Rui Paulo wrote: > >> On Aug 20, 2014, at 22:34, Evandro Nunes >> wrote: >> >> > On Thu, Aug 21, 2014 at 2:05 AM, Rui Paulo wrote: >> > On Aug 20, 2014, at 21:52, Evandro Nunes >> wrote: >> > >> > > On Thu, Aug 21, 2014 at 1:51 AM, Rui Paulo >> wrote: >> > > On Aug 20, 2014, at 21:48, Evandro Nunes >> wrote: >> > > >> > > > hello, >> > > > >> > > > ive got a ultrasonic sensor model HC-SR04 and a beaglebone black as >> well as >> > > > a cubieboard2, both running FreeBSD 11 built from crochet and wiki >> > > > instructions >> > > > >> > > > thanks to the help from loos@ I could manage to use a 5v relay >> with BBB >> > > > now, how can I read data from HC-SR04 sensor? do we have any library >> > > > available? or do we have any GPIO utility to do that? >> > > > btw how can I read values from GPIO pins when they are set to input? >> > > >> > > I wrote a library to handle GPIO on FreeBSD: >> > > >> > > https://bitbucket.org/rpaulo/libgpio >> > > >> > > very good :-) I will play with that >> > > >> > > You can also use the gpioctl utility in FreeBSD to read values. >> > > >> > > how? can you point me to any further reading, blog entry, or examples? >> > >> > There's a man page, but "gpioctl -c IN" will set the pin in input >> mode. Then, "gpioctl " will read the value. >> > >> > so this way I should read something from HC-SR04 echo pin on BBB? >> > I am using another gpio pin in output mode as a trigger, according to >> what I've read, 3.3v is OK as a trigger for this sonar >> > >> > but when I read the GPIO pin in input mode just as you mentioned, I >> always get a 0 value... >> > I am using BBB's P9_1 and P9_5 for +5v and ground, P9_21 as a trigger >> and P9_23 as echo; set GPIO 3 (P9_21) as output and GPIO 49 (P9_23) as input >> > I made a loop to read GPIO 49 every 100ms and another loop to trigger >> (gpioctl -t 3; sleep .100; gpioctl -t 3) every 2 seconds. >> > >> > what I am doing wrong? feeding 3.3v for 0.1 seconds as a trigger >> should't cause something to echo? >> >> Don't you have a multimeter? Have you measured the voltage on the output >> pin when you switch it to 0 and then back to 1? >> > > no, I don't have a working multimeter, mine is dead. I will buy another > one and test it as suggested, yes you are right, although I dont have an > idea on what value it should be expected > > but for curiosity, will gpioctl 49 show values anyhow equivalent to what a > multimeter would display? or I should not expect anything similar? > sorry for that question if this is too dummy, yes I completely lack on > GPIO basics, it's my first experience rss > > > > > >> -- >> Rui Paulo >> >> >> >> >