Hey all, I'm using the Debian Jessie image with kernel version 4.4.6-ti-r15 on my BeagleBone Black.
To monitor our vacuum system in the lab, we need a RS485 interface, so I simply connected an ADM2682 RS422/485 line driver to UART4 of the BeagleBone using this Device Tree Overlay BB-UART4-RS485-00A0.dts <https://github.com/RobertCNelson/bb.org-overlays/blob/master/src/arm/BB-UART4-RS485-00A0.dts> (commit 16f76f7 on master branch) P9.27 is connected to the DE and !RE inputs of the chip. Using this for sending works just fine, but I have problems receiving messages over the bus. For testing I wrote a small C-program which should read on the bus until it gets two times a timeout. The reading is done via select-call with a 5 second timeout. The device on the other end of the bus is contentiously sending data over the bus. After receiving 49 bytes at most, the DE/!RE line goes up and my BeagleBone stops receiving any data... I've uploaded a screenshot of the scope showing the three signals from the UART interface Scope <http://www.ep1.rub.de/~florian/rs485.png> Does anyone has a clue what could go wrong? Any help appreciated! Regards Florian -- 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/e85a762f-6e2a-4505-b064-5840b27a343f%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
