On 23/04/16 01:18, cjvijf at gmail.com wrote: > Hello, > > I am running Centos on a raspberry pi 2b. (I downloaded the image from: > http://people.centos.org/hughesjr/armv7hl/rpi2/images/ > rpi2-centos-image.img.xz ) > and installed the i2c libraries and modules for i2c. > [root at rpi2-2 ~]# lsmod | grep i2c > > i2c_bcm2708 5006 0 > i2c_dev 6027 0 > > From what I read that should be correct > > device file is there too: > crw------- 1 root root 89, 1 Dec 31 1969 i2c-1 > > kernel: > Linux rpi2-2 3.18.14-v7+ #794 SMP PREEMPT Sun Jun 7 12:50:51 BST 2015 > armv7l armv7l armv7l GNU/Linux > > > However, when I scan the i2c bus with 'i2cdetect -y 1' I don't see any > devices (and I tried 2 that I know work). > > is the I2C stuff in this kernel working? (or is there a newer kernel > version?) > > thanks, > > Ron > > > P.S. I know this is an arm-dev list, but figured the I2C topic would > fit better here than in a general Centos list > I know it's a very old post, but I had to search for a friend of mine, using CentOS 7.3.1611 on his rpi2 , so here we go : We need to activate it through config.txt : echo -e "dtparam=i2c1=on\ndtparam=i2c_arm=on" >> /boot/config.txt echo -e "i2c-bcm2708\ni2c-dev" >> /etc/modules-load.d/i2c.conf yum install -y i2c-tools systemctl reboot Once rebooted : [root at rpi2 ~]# i2cdetect -y 1 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- -- Fabian Arrotin The CentOS Project | http://www.centos.org gpg key: 56BEC54E | twitter: @arrfab -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: OpenPGP digital signature URL: <http://lists.centos.org/pipermail/arm-dev/attachments/20170129/829bbd5d/attachment-0005.sig>