On Sat, Jun 17, 2017 at 11:51 PM, mark whitney <[email protected]> wrote: > Hello, > > I'm trying to work through the I2C examples in the Molloy book. But I'm > using a Honeywell HMC6352 compass since I had one lying around. It can work > from 2.7V to 5V and operates at a bus frequency of 100KHz. I verified that > it works by hooking it up to a 5V microcontroller. I can query its > registers. But I haven't had any luck communicating with it on a BeagleBone > Black. > > I'm using 3.9V pull-up resistors for SDA and SCL. Here is info about my > kernel version, cape slots, and the I2C pins: > > debian@beaglebone:~$ uname -a > Linux beaglebone 4.4.54-bone16 #1 Fri Mar 17 04:56:31 UTC 2017 armv7l > GNU/Linux > debian@beaglebone:~$ sudo cat $SLOTS > 0: PF---- -1 > 1: PF---- -1 > 2: PF---- -1 > 3: PF---- -1 > 4: P-O-L- 0 Override Board Name,00A0,Override Manuf,cape-universaln > debian@beaglebone:~$ config-pin -i P9.19 > Pin is not modifyable: P9_19 i2c2_scl > debian@beaglebone:~$ config-pin -i P9.20 > Pin is not modifyable: P9_20 i2c2_sda > debian@beaglebone:~$ > > It looks like everything is okay. Am I missing any steps? I saw some info > about adding an I2C overlay. Is that still necessary with the universal > cape? > > BTW, I also tried the 4.4.54-ti-r93 kernel without success. > > Thanks for any advice. This noob is stumped. :-)
the i2c port on P9_19/P9_20 is already enabled by default. 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/CAOCHtYh3JNpsbutBNq_FHASJ7WAHtev7MsxYH%2BWPiRMPptE3Hw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
