p.s. - I'm currently running a patched version of kernel version 4.4.110...
On Monday, March 5, 2018 at 9:12:06 AM UTC-6, Jeff Andich wrote: > > Hi, > > There have been a number of posts on here on how to switch between the > 8250 and OMAP drivers. Above in this same thread, Robert showed which > defines within the kernel defconfig file to change, and I experimented with > this and was able to see and use /dev/ttyO* instead of /dev/ttyS*. I had > to search for and swtich additional defines, as initially, I ended-up > losing my console and still had /dev/ttyS*.. If you look through the > following post, you can see how I switched from the 8250 to the OMAP > driver. Someone else on here proposed a way to have a mixture of OMAP and > 8250 serial drivers, but I haven't been brave enough to try that yet. > > https://groups.google.com/forum/#!topic/beagleboard/JGIm0Ej6jDI > > I never attempted to get full-blown hardware flow control up and running, > since our hardware board has RS485 chips which only have the DE pin > connected. RTS and CTS lines don't interconnect the different parties on > the MODBUS network in our case, only the RS485 differential signals (e.g. > TXp, TXn). > > Initially we connected GPIO lines to the DE pins, but then more recently, > our hardware engineer swapped out GPIO lines for the "dedicated RTS" line > for a given UART. > > One thing that's really interesting, IMO, is if you use a dedicated RTS > line (e.g. UART5 RTSn), you can still toggle RTS from the application layer > **using the 8250 driver**. Whereas when I attempted to use a GPIO line > and couple that to the UART through the UART device tree fragment (refer to > the above thread for an example), I was not able to toggle the RTS line > with the 8250 serial driver, but only the OMAP serial driver. So as a test > I installed python-serial on my beagleBoard-X15. When I issued > serial_object.setRTS(False/True) which was connected to DE on the 485 chip, > I would see the chip transmit and not transmit using the 8250 driver. But > when using the GPIO line for RTS, I could only switch between transmit and > receive on the 485 chip when I compiled in and used the OMAP drivers. > > On Monday, March 5, 2018 at 7:12:50 AM UTC-6, erc...@gmail.com wrote: >> >> Hi Micka, >> >> We are having lots of trouble with RS485 with Kernel 4.4.x or kernel >> 3.8.13. >> >> Is there any guideline about how to use OMAP rather than 8250 or can you >> please explain the steps how can we do that? >> >> On Tuesday, April 26, 2016 at 10:00:19 AM UTC+3, Micka wrote: >>> >>> I dont know about 8250, but omap work well. I'm more confident about >>> omap handling the gpio than the driver 8250. >>> >>> I've been using omap for rs485 since the driver 3.8 and I've nothing to >>> complain about. >>> >>> I will also switch to the driver 8250 when it will be ready ( a lot of >>> test need to be done ) >>> >>> >>> Micka, >>> >>> >>> >>> Le mar. 26 avr. 2016 08:05, 'Artur Festyn' via BeagleBoard < >>> beagl...@googlegroups.com> a écrit : >>> >>>> Hi Micka. >>>> no ttyO, its 8250 driver. >>>> shouldn't 4.5 kernel work after these patches are applied or is it >>>> still too early? >>>> >>>> -rw-r--r-- 1 root root 1440 Apr 21 12:26 >>>> 0001-tty-serial-8250-fix-RS485-half-duplex-RX.patch >>>> -rw-r--r-- 1 root root 8243 Apr 21 12:26 >>>> 0002-tty-serial-8250-make-UART_MCR-register-access-consis.patch >>>> -rw-r--r-- 1 root root 2743 Apr 21 12:26 >>>> 0003-serial-mctrl_gpio-add-modem-control-read-routine.patch >>>> -rw-r--r-- 1 root root 1347 Apr 21 12:26 >>>> 0004-serial-mctrl_gpio-add-IRQ-locking.patch >>>> -rw-r--r-- 1 root root 7924 Apr 21 12:26 >>>> 0005-tty-serial-8250-use-mctrl_gpio-helpers.patch >>>> >>>> the last one clearly states that use of any gpio as rts should be >>>> possible >>>> >>>> >>>> 2016-04-26 6:54 GMT+01:00 Micka <micka...@gmail.com>: >>>> >>>>> Can you show me what this command show : >>>>> >>>>> dmesg|grep ttyO* >>>>> >>>>> I repeat only omap driver work for rs485 >>>>> >>>>> Le mar. 26 avr. 2016 00:40, 'Artur Festyn' via BeagleBoard < >>>>> beagl...@googlegroups.com> a écrit : >>>>> >>>>>> It is easy and already disabled. >>>>>> My question is about RS485 and custom gpio to drive DE pin of RS485 >>>>>> chip. >>>>>> >>>>>> >>>>>> 2016-04-25 23:22 GMT+01:00 evilwulfie <evilw...@gmail.com>: >>>>>> >>>>>>> read this. disabling I2C2 is not as easy as using an overlay >>>>>>> if you are not using capes sure but IMHO is always best to leave the >>>>>>> default things enabled and just work with overlays >>>>>>> >>>>>>> >>>>>>> http://www.embedded-things.com/bbb/enable-canbus-on-the-beaglebone-black/ >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 4/25/2016 2:09 PM, 'Artur Festyn' via BeagleBoard wrote: >>>>>>> >>>>>>> Honestly I don't know. I though this might be useful info :) >>>>>>> Three is no problem to disable I2C-2, but I am using those pins for >>>>>>> CAN0. >>>>>>> That is why I want to use custom gpio to drive RS485 DE which >>>>>>> doesn't work. >>>>>>> >>>>>>> 2016-04-25 21:56 GMT+01:00 William Hermans <yyr...@gmail.com>: >>>>>>> >>>>>>>> *cat /proc/tty/driver/serial* >>>>>>>> >>>>>>>> *serinfo:1.0 driver revision:* >>>>>>>> *0: uart:8250 mmio:0x44E09000 irq:158 tx:2451 rx:0 RTS|CTS|DTR|DSR* >>>>>>>> *1: uart:8250 mmio:0x48022000 irq:159 tx:24 rx:0 CTS|DSR|CD|RI* >>>>>>>> *2: uart:8250 mmio:0x48024000 irq:160 tx:0 rx:0 CTS|DSR* >>>>>>>> *3: uart:unknown port:00000000 irq:0* >>>>>>>> *4: uart:8250 mmio:0x481A8000 irq:161 tx:2 rx:1 brk:1 CTS|DSR* >>>>>>>> >>>>>>>> *5: uart:unknown port:00000000 irq:0* >>>>>>>> >>>>>>>> What is this supposed to mean ? That says UART0 has RTS, CTS, etc, >>>>>>>> but they're not connected to anything. So the CTS on UART1 means >>>>>>>> nothing. >>>>>>>> Because it's connected to I2C-2, which I'm sure you would have all >>>>>>>> kinds of >>>>>>>> fun disabling I2C-2 . . . >>>>>>>> >>>>>>>> >>>>>>>> On Mon, Apr 25, 2016 at 1:14 PM, 'Artur Festyn' via BeagleBoard < >>>>>>>> beagl...@googlegroups.com> wrote: >>>>>>>> >>>>>>>>> cat /proc/tty/driver/serial >>>>>>>>> serinfo:1.0 driver revision: >>>>>>>>> 0: uart:8250 mmio:0x44E09000 irq:158 tx:2451 rx:0 RTS|CTS|DTR|DSR >>>>>>>>> *1: uart:8250 mmio:0x48022000 irq:159 tx:24 rx:0 CTS|DSR|CD|RI* >>>>>>>>> 2: uart:8250 mmio:0x48024000 irq:160 tx:0 rx:0 CTS|DSR >>>>>>>>> 3: uart:unknown port:00000000 irq:0 >>>>>>>>> 4: uart:8250 mmio:0x481A8000 irq:161 tx:2 rx:1 brk:1 CTS|DSR >>>>>>>>> 5: uart:unknown port:00000000 irq:0 >>>>>>>>> >>>>>>>>> >>>>>>>>> 2016-04-25 21:12 GMT+01:00 Artur Festyn <fes...@googlemail.com>: >>>>>>>>> >>>>>>>>>> I can't use RTS/CTS pins on UART4 because I need HDMI. >>>>>>>>>> New RS485 patches suppose to help to use any gpio as RS485 RTS >>>>>>>>>> and in fact any gpio for any UART as RTS/CTS. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> 2016-04-25 21:00 GMT+01:00 evilwulfie <evilw...@gmail.com>: >>>>>>>>>> >>>>>>>>>>> any reason you want to use uart1 ? >>>>>>>>>>> >>>>>>>>>>> if you use uart4 you can use the whole uart tx rx and rts. >>>>>>>>>>> trying to bitbang rts for rs485 on uart1 sounds hard >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On 4/25/2016 12:24 PM, 'Jan Kinkazu' via BeagleBoard wrote: >>>>>>>>>>> >>>>>>>>>>> So i compiled (bb-kernel, all patches) and installed >>>>>>>>>>> 4.5.2-bone4 >>>>>>>>>>> I have modified am335-boneblack.dts and compiled it. >>>>>>>>>>> >>>>>>>>>>> #include "am335x-peripheral-ttyS1.dtsi" >>>>>>>>>>> #include "am335x-bone-pinmux-ttyS1.dtsi" >>>>>>>>>>> >>>>>>>>>>> &am33xx_pinmux { >>>>>>>>>>> uart1_pins: pinmux_uart1_pins { >>>>>>>>>>> pinctrl-single,pins = < >>>>>>>>>>> /* P9_23: uart1_de */ >>>>>>>>>>> BONE_P9_23 (PIN_OUTPUT_PULLDOWN | >>>>>>>>>>> MUX_MODE7) >>>>>>>>>>> >; >>>>>>>>>>> }; >>>>>>>>>>> }; >>>>>>>>>>> >>>>>>>>>>> &uart1 { >>>>>>>>>>> pinctrl-names = "default"; >>>>>>>>>>> pinctrl-0 = <&uart1_pins>; >>>>>>>>>>> status = "okay"; >>>>>>>>>>> rts-gpios = <&gpio1 17 GPIO_ACTIVE_HIGH>; >>>>>>>>>>> rs485-rts-active-high; >>>>>>>>>>> rs485-rx-during-tx; >>>>>>>>>>> rs485-rts-delay = <1 1>; >>>>>>>>>>> linux,rs485-enabled-at-boot-time; >>>>>>>>>>> }; >>>>>>>>>>> >>>>>>>>>>> RS485 doesn't work, what do I do wrong? >>>>>>>>>>> >>>>>>>>>>> Kind regards >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Friday, 12 February 2016 15:33:40 UTC, Taceant Omnes wrote: >>>>>>>>>>>> >>>>>>>>>>>> I would like to use RS485 with the BBB. >>>>>>>>>>>> >>>>>>>>>>>> root@beaglebone:~/test# uname -a >>>>>>>>>>>> Linux beaglebone 4.1.15-ti-r40 #1 SMP PREEMPT Thu Jan 7 >>>>>>>>>>>> 23:32:17 UTC >>>>>>>>>>>> 2016 armv7l GNU/Linux >>>>>>>>>>>> >>>>>>>>>>>> I am using the kernel above. Its source code is at >>>>>>>>>>>> >>>>>>>>>>>> <https://github.com/RobertCNelson/linux-stable-rcn-ee/tree/4.1.15-ti-rt-r40> >>>>>>>>>>>> https://github.com/RobertCNelson/linux-stable-rcn-ee/tree/4.1.15-ti-rt-r40 >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> ... however it does not include the changes in this patch: >>>>>>>>>>>> >>>>>>>>>>>> <https://github.com/RobertCNelson/bb-kernel/blob/am33x-v3.8/patches/fixes/0007-omap-RS485-support-by-Michael-Musset.patch#L30> >>>>>>>>>>>> https://github.com/RobertCNelson/bb-kernel/blob/am33x-v3.8/patches/fixes/0007-omap-RS485-support-by-Michael-Musset.patch#L30 >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Which kernel should I use that includes the changes in the >>>>>>>>>>>> patch or >>>>>>>>>>>> something similar? >>>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> For more options, visit <http://beagleboard.org/discuss> >>>>>>>>>>> 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 beagleboard...@googlegroups.com. >>>>>>>>>>> To view this discussion on the web visit >>>>>>>>>>> <https://groups.google.com/d/msgid/beagleboard/50692f39-69e3-4454-b8ba-ec03e4d86101%40googlegroups.com> >>>>>>>>>>> https://groups.google.com/d/msgid/beagleboard/50692f39-69e3-4454-b8ba-ec03e4d86101%40googlegroups.com >>>>>>>>>>> . >>>>>>>>>>> For more options, visit <https://groups.google.com/d/optout> >>>>>>>>>>> https://groups.google.com/d/optout. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient&utm_term=icon> >>>>>>>>>>> Virus-free. >>>>>>>>>>> >>>>>>>>>>> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient&utm_term=link> >>>>>>>>>>> www.avast.com >>>>>>>>>>> -- >>>>>>>>>>> For more options, visit <http://beagleboard.org/discuss> >>>>>>>>>>> http://beagleboard.org/discuss >>>>>>>>>>> --- >>>>>>>>>>> You received this message because you are subscribed to a topic >>>>>>>>>>> in the Google Groups "BeagleBoard" group. >>>>>>>>>>> To unsubscribe from this topic, visit >>>>>>>>>>> <https://groups.google.com/d/topic/beagleboard/nMtRpdWSJu0/unsubscribe> >>>>>>>>>>> https://groups.google.com/d/topic/beagleboard/nMtRpdWSJu0/unsubscribe >>>>>>>>>>> . >>>>>>>>>>> To unsubscribe from this group and all its topics, send an email >>>>>>>>>>> to beagleboard...@googlegroups.com. >>>>>>>>>>> To view this discussion on the web visit >>>>>>>>>>> <https://groups.google.com/d/msgid/beagleboard/571E7751.2020206%40gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>>>> https://groups.google.com/d/msgid/beagleboard/571E7751.2020206%40gmail.com. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> For more options, visit <https://groups.google.com/d/optout> >>>>>>>>>>> https://groups.google.com/d/optout. >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> -- >>>>>>>>> For more options, visit <http://beagleboard.org/discuss> >>>>>>>>> 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 beagleboard...@googlegroups.com. >>>>>>>>> To view this discussion on the web visit <a href=" >>>>>>>>> https://groups.google.com/d/msgid/beagleboard/CAAPjYCaM58KxhqX_s1DwsdJ7z2tdemEoCVHjZj0D780CpxQTug%40mail.gmail.com?utm_medium=email&utm_source=footer"; >>>>>>>>> >>>>>>>>> target="_blank" rel="nofollow" onmousedown="this.href='<a href=" >>>>>>>>> https://groups.google.com/d/msgid/beagleboard/CAAPjYCaM58KxhqX_s1DwsdJ7z2td >>>>>>>> >>>>>>>> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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