On Sun, Jun 18, 2017 at 10:59 AM, mark whitney <[email protected]> wrote: > Thank you for the reply. > > As a sanity check, I went back to Debian 7.5. And it just worked without > having to do any extra configuration. See below for a dump of results. My > compass device appears at its default address 0x21. I sent a command (0x72) > to read EEPROM register 0x00 and read back the expected byte (0x42). > > With the Debian 8.7 image, I got error messages when I tried the i2cget and > i2cset commands. I also noticed that the i2cdetect -y -r 1 command runs > very slowly compared to the Debian 7.5 image, it takes a second or so to > print each address entry. > > Is there some extra configuration I need to do in Debian 8.7? Like edit the > uEnv.txt file? Load an overlay? Or tweak a DTS file? > > Thanks! > > > debian@beaglebone:~$ uname -a > Linux beaglebone 3.8.13-bone50 #1 SMP Tue May 13 13:24:52 UTC 2014 armv7l > GNU/Linux > debian@beaglebone:~$ i2cdetect -y -r 1 > 0 1 2 3 4 5 6 7 8 9 a b c d e f > 00: -- -- -- -- -- -- -- -- -- -- -- -- -- > 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 20: -- 21 -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 50: -- -- -- -- UU UU UU UU -- -- -- -- -- -- -- -- > 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 70: -- -- -- -- -- -- -- -- > debian@beaglebone:~$ i2cset -y 1 0x21 0x72 0x00 > debian@beaglebone:~$ i2cget -y 1 0x21 > 0x42
Wrong bus.. With 3.8.13 the i2c bus #'s where setup on a first come basis.. With newer kernel's the bus #'s actually corresponds to the i2c bus #.. In this case: &i2c2.. So use: i2cdetect -y -r 2 Regards, -- Robert Nelson https://rcn-ee.com/ -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAOCHtYi%3DX25tHdpSMZo9abfdSZzbeidzbDK9_HDVq85%3D-52SjQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
