There is no problem with the kernel 4.4 and rs485. Just use the omap driver and not the 8250 driver. It works well for me since 4 years.
Le ven. 24 mars 2017 11:24, <[email protected]> a écrit : > Hi, > > We are having allot of problems getting RS485 with RTS working on Debian: > Linux 4.4 > CAn someone help? > > > On Thursday, March 23, 2017 at 9:13:23 PM UTC+2, [email protected] wrote: > > Hi Alexander, > > The link you provided does not work: > > > http://inspire.logicsupply.com/2014/09/beaglebone-rs-485-communication.html > > > Do you mind sending me the tutorial? I am currently designing my own cape > which will support two RS485 half duplex channels and your tutorial would > be very helpful to get me started. My questions are: > > 1) Am I limited to UART4 or can I use any of the available UARTs on the > Beaglebone Black? > > 2) Just to be 100% sure, I can use any of the GPIO pins for controlling DE > & /RE pins on the RS485 transceiver (I'm using TI's ISO15MDW)? > > Thank you, > > Bolek > > On Wednesday, September 3, 2014 at 10:07:26 AM UTC-7, Alexander Hiam wrote: > > I actually just put up a tutorial for doing this in Python: > http://inspire.logicsupply.com/2014/09/beaglebone-rs-485-communication.html > > It uses GPIO1_16, but of course you can use any GPIO pin, including the > one that's shared with UART4 RTS. > > > When I tried to use: > struct serial_rs485 rs485conf; > rs485conf.flags |= SER_RS485_USE_GPIO; > rs485conf.gpio_pin = GPIO0_9; > > I got error from gcc that it does not know those macros: > ‘SER_RS485_USE_GPIO’ was not declared in this scope > rs485conf.flags |= SER_RS485_USE_GPIO; > ‘struct serial_rs485’ has no member named ‘gpio_pin’ > rs485conf.gpio_pin = GPIO0_9; > ‘GPIO0_9’ was not declared in this scope > rs485conf.gpio_pin = GPIO0_9; > > > That's because you're compiling with the standard libc headers, which > don't include the modified serial_rs485 struct that uses the GPIO pin. The > tutorial I linked above uses Python and just defines the same values > locally, which you could do in C as well. You could also grab the Kernel > source and include 'include/uapi/linux/serial.h', which has the patched > serial_rs485 struct ( > https://github.com/RobertCNelson/bb-kernel/blob/am33x-v3.8/patches/fixes/0007-omap-RS485-support-by-Michael-Musset.patch#L201 > ). > > -- > 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/128d1fae-46ac-4e2d-a759-1cb1568f443c%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/128d1fae-46ac-4e2d-a759-1cb1568f443c%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- 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/CAF%2BMRtnVGeQN9qVW7Msi4u3C1YfErKUf8E0Ve1S9%2BGX2nq-1KA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
