In the Debian image from Robert C Nelson, the patch rs485 is already included. Le 4 sept. 2014 20:57, <lucaso.ja...@gmail.com> a écrit :
> Thank you for your answers. The python code is working perfectly. > I need to use it in greater C project though. So I am compiling new kernel > including RS485 patch. I have tried /opt/scripts/tools/update_kernel.sh > hoping that it includes the RS485 patch ...unsuccessfully. > I am now following steps from > http://jkridner.wordpress.com/2014/06/04/yet-another-set-of-notes-on-building-beaglebone-kernel/ > > Dne středa, 3. září 2014 17:57:53 UTC+2 lucaso...@gmail.com napsal(a): >> >> Hello, >> I'm writing an app for BeagleBoneBlack running debian (3.8.13-bone50). I >> would like to use UART4 to communicate with RS485 transmitter over >> P9.24(UART4 Tx), P9.26(UART4 Rx) and P8.33 (UART4 RTS). >> I've disabled HDMI and enabled overlays BB-UART4 and BB-UART4-RTSCTS >> >> cat /sys/devices/bone_capemgr.9/slots >> 0: 54:PF--- >> 1: 55:PF--- >> 2: 56:PF--- >> 3: 57:PF--- >> 4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G >> 5: ff:P-O-- Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI >> 6: ff:P-O-- Bone-Black-HDMIN,00A0,Texas Instrument,BB-BONELT-HDMIN >> 7: ff:P-O-L Override Board Name,00A0,Override Manuf,BB-UART4 >> 10: ff:P-O-L Override Board Name,00A0,Override Manuf,BB-UART4-RTSCTS >> >> cat /proc/tty/driver/OMAP-SERIAL >> serinfo:1.0 driver revision: >> 0: uart:OMAP UART0 mmio:0x44E09000 irq:72 tx:345 rx:0 RTS|CTS|DTR|DSR >> 4: uart:OMAP UART4 mmio:0x481A8000 irq:45 tx:61355 rx:1 brk:1 RTS|DTR|DSR >> >> >> RS485 transmitter is connected through RS485-USB converter to PC. When I >> run screen /dev/ttyO4 9600 +crtscts and periodicaly write some data to it, >> PC receives it properly, but RTS line stays constantly low (I'm using scope >> on Tx and RTS lines). >> I've also tried to write simple C program, using *struct serial_rs485. *When >> I write some data over this program, I got response: *Resource >> temporarily unavailable* and dmesg says >> *omap_uart 481a8000.serial: Must use GPIO for RS485 Support.*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; >> >> Could somebody help me? I have no more ideas. >> >> >> >> >> >> -- > 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 beagleboard+unsubscr...@googlegroups.com. > 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
