This also worked for me, I have spent days and days on this , thank you so much.
There are so many config issues that this could be I can't tell you how many paths I went down, so many dtbo files that might change something or break, kernel options etc , again THANKS. On Tuesday, February 6, 2018 at 6:51:14 AM UTC-6, [email protected] wrote: > > rituku thank you so much!! > I tried so many things but only the uboot_overlay lines made it work. > > Le jeudi 9 février 2017 21:30:23 UTC+9, Patrick Oetken a écrit : >> >> Hello! >> >> I'm trying to use the BeagleBone Black to communicate to RS485 and >> CAN-Devices. >> For testing I ordered the Waveshare RS485-CAN Cape >> <http://www.waveshare.com/rs485-can-cape.htm>. Later on the MAX13487 >> should be used for RS485 at UART2. CAN works fine using the BB-CAN1 overlay >> with uEnv.txt (UART1). >> >> But first I tried to communicate from UART1 to UART2, to check if the >> UARTs are working. I added BB-UART1, BB-UART2 and BB-UART4 to uEnv.txt and >> connected UART1 RX to UART2 TX and UART1 TX to UART2 RX (Pins 22 and 24/ 26 >> and 21). >> >> After Reboot, the UARTs are activated: >> >> root@beaglebone:/# ls -l /dev/ttyO* >> lrwxrwxrwx 1 root root 5 Feb 7 13:55 /dev/ttyO0 -> ttyS0 >> lrwxrwxrwx 1 root root 5 Feb 7 13:55 /dev/ttyO1 -> ttyS1 >> lrwxrwxrwx 1 root root 5 Feb 7 13:55 /dev/ttyO2 -> ttyS2 >> lrwxrwxrwx 1 root root 5 Feb 7 13:55 /dev/ttyO4 -> ttyS4 >> >> root@beaglebone:/# dmesg | grep tty >> [ 0.000000] Kernel command line: console=tty0 console=ttyO0,115200n8 >> capemgr.enable_partno=BB-UART1,BB-UART2,BB-UART4, BB-UART5 >> root=/dev/mmcblk0p1 >> rootfstype=ext4 rootwait coherent_pool=1M quiet cape_universal=enable >> [ 0.001090] console [tty0] enabled >> [ 0.001109] WARNING: Your 'console=ttyO0' has been replaced by 'ttyS0' >> [ 3.929029] 44e09000.serial: ttyS0 at MMIO 0x44e09000 (irq = 158, >> base_baud = 3000000) is a 8250 >> [ 3.941849] console [ttyS0] enabled >> [ 22.142299] 48022000.serial: ttyS1 at MMIO 0x48022000 (irq = 189, >> base_baud = 3000000) is a 8250 >> [ 22.154538] 48024000.serial: ttyS2 at MMIO 0x48024000 (irq = 190, >> base_baud = 3000000) is a 8250 >> [ 22.165780] 481a8000.serial: ttyS4 at MMIO 0x481a8000 (irq = 191, >> base_baud = 3000000) is a 8250 >> >> Most tutorials using an older Debian version are using ttyOx to access >> the serial ports (old OMAP-driver?), but based on this output I have to use >> ttySx with the newer 8250 driver for my commands instead? >> >> I tried to send/receive messages between the UARTs using minicom, screen >> and python scripts, but i can't see any messages at the receiving >> interface. Measuring the sending UARTs TX with an oscilloscope I also can't >> see any signals. >> >> At the moment I am running Debian Image 2016-05-13 with Kernel >> 4.9.8-bone-rt-r4, I also tried everything with the original Kernel of this >> Image (4.4.9?) and a fresh Debian IoT Image 2016-12-09 and also with >> UART2+UART4. >> >> Is there any missing configuration I have to do to get it working? >> >> -- 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/c6ce8013-1dde-4058-b6c7-a1783c15fc73%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
