lsmod

Yes - but the organisation of this schematic diagram is horrible. It would be nice to have a complete overview. A helpful table can be found on page 23 of the CPU description: http://linux-sunxi.org/images/d/de/Allwinner_H5_Datasheet_V1.0.pdf

But - why? pin 23/24 is shown in the diagram as SPI1? Is the reason that this pins are multi purpose? Where did you find this secret?

My experiment to activate UART0 fails with overlays=... uart0 uart1 and results only in an working UART1. O.K. - then i have to connect my serial device on UART 1 and everything is fine. Thank you for your help martinayotte! Is it possible to use the UART pin's near the HDMI-connector?

Hmm - this information comes late. Additional i have to find out that an overlay assignment is already existant from the beginning! This is the content of the original file armbianEnv.txt that is again in use: verbosity=1 console=both overlay_prefix=sun50i-h5 rootdev=UUID=aa5e51f4-5867-45a3-a342-740ba0961be3 rootfstype=ext4 overlays=analog-codec i2c0 i2c1 i2c2 pps-gpio pwm spi-add-cs1 spi-jedec-nor spi-spidev uart1 uart2 uart3 w1-gpio usbstoragequirks=0x2537:0x1066:u,0x2537:0x1068:u The problem is that all UART's should have worked from the beginning! Retest of the UART with a wire-loop now: UART1 on GPIO pin 38/40 -> working loop! UART2 on GPIO pin 11/13 -> working loop! UART3 on GPIO pin 8/10 -> NOT working loop! -> then wrong pins will be a good explanation! O.K. - now i know why my connection on pin 8/10 did not work from the beginning. What is the meaning of TXD0 and RXD0 ? dmesg now shows: [ 0.707241] 1c28400.serial: ttyS1 at MMIO 0x1c28400 (irq = 28, base_baud = 1500000) is a U6_16550A [ 0.729886] 1c28800.serial: ttyS2 at MMIO 0x1c28800 (irq = 29, base_baud = 1500000) is a U6_16550A [ 0.752520] 1c28c00.serial: ttyS3 at MMIO 0x1c28c00 (irq = 30, base_baud = 1500000) is a U6_16550A

I see in the manual that this should be UART3. And i can see on page 6 in GPIO of the schematic that UART3 should be PA14/PA13. That was the source. It takes more than one minute for me. But i know what you mean - this days i simply don't have enough time for this problem and i always must "think me into the problem again". Now i checked with and without a wire-loop on GIPO pins 38+40 that should be UART1. I added to the configuration overlays=uart1 overlays=uart2 UART1 can't be opened with a serial program. UART2 can be opened, but there is no echo with a wire-loop. It's the same when i short pin 11+13 with a wire-loop. No echo for UART2. You see - the UART's of the H5 are dead and can't be used within Armbian! There are no error messages within the serial programs or dmesg - simply dead. It's a pity - when i want to have an serial port i must block one USB-port and plug in an PL2303 converter - that works.

When it is clear enough - why there is UART0 on Pin 8/10 ? UART0 is defined on PA4/PA5 in the configuration files ? I already tested UART0 and it is not working too I think i have to give up to get the UART working with Armbian on an Orange Pi PC 2 ...

This schematic does not contain a clear and reliable Pinout.! Correct. I have wirtten that there was no signal. This are serial Pins on an Raspberry - so why not on an Orange-Pi ?

Now i am very confused. Where you find this information about Pins 23/24 ? We already discussed this theme here and i have to find out that every Pinout is somehow wrong! Is there somewhere a correct one for an Orange Pi PC 2 ? But your idea is good - i will make simple tests just to find any working UART ... The scope probe was O.K., because i could see High-Level 3.3V and working signal of the serial device i want to connect.

Good idea! It seems that the serial ports are added with the correct number: [ 0.682731] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled [ 0.683890] console [ttyS0] disabled [ 0.704033] 1c28000.serial: ttyS0 at MMIO 0x1c28000 (irq = 28, base_baud = 1500000) is a U6_16550A [ 0.704085] console [ttyS0] enabled [ 0.726793] 1c28c00.serial: ttyS3 at MMIO 0x1c28c00 (irq = 29, base_baud = 1500000) is a U6_16550A I can only open /dev/ttyS3. All other ports will fail with "Unable to configure serial port" When i enable all ports with overlays=uart2 overlays=uart3 overlays=uart4 then i get none of the ports active and all fail to configure! dmesg shows: [ 0.000000] Kernel command line: root=UUID=aa5e51f4-5867-45a3-a342-740ba0961be3 rootwait rootfstype=ext4 console=tty1 console=ttyS0,115200 panic=10 consoleblank=0 loglevel=1 ubootpart=1968c433-01 usb-storage.quirks=0x2537:0x1066:u,0x2537:0x1068:u cgroup_enable=memory swapaccount=1 ... [ 0.682140] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled [ 0.683293] console [ttyS0] disabled [ 0.703433] 1c28000.serial: ttyS0 at MMIO 0x1c28000 (irq = 28, base_baud = 1500000) is a U6_16550A [ 0.703483] console [ttyS0] enabled The first kernel message is missing when only uart3 is active. I returned to this configuration where only UART3 is configured in /boot/armbianEnv.txt It is also possible to check the configuration of the serial port: # stty -aF /dev/ttyS3 speed 9600 baud; rows 0; columns 0; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 0; time = 0; -parenb -parodd -cmspar cs8 hupcl -cstopb cread clocal -crtscts -ignbrk -brkint ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -iutf8 -opost -olcuc -ocrnl -onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 -isig -icanon -iexten -echo -echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke -flusho -extproc My last experiment was to change RXD and TXD to be sure that it is not connected wrong. But of course it does not make a difference - data is not coming in! Additional i send a file with cutecom over /dev/ttyS3, but i could see no signal on TXD with an oscillloscope. I have no further idea ...

This is my current Pin-Assignment for the GPIO with all references:

Yes - i can find this files in the path /boot/dtb/allwinner/overlay -rw-r--r-- 1 root root 506 Sep 19 12:10 sun50i-a64-uart1.dtbo -rw-r--r-- 1 root root 1001 Sep 19 12:10 sun50i-a64-uart2.dtbo -rw-r--r-- 1 root root 826 Sep 19 12:10 sun50i-a64-uart3.dtbo -rw-r--r-- 1 root root 1001 Sep 19 12:10 sun50i-a64-uart4.dtbo For other users: The files can be translated each with dtc -I dtb sun50i-a64-uart1.dtbo -O dts -o sun50i-a64-uart1.dts There are many definitions for the UART ... Yes - i am really confused by the wrong schematics. Is there anywhere an complete correct Pin-Assignment? I want to connect my serial device to Pin 8 and 10 of the GPIO. I can see with an oscilloscope that there is data on Pin 10 of the GPIO which should be RXD of UART3 (PA14). Is this assignment correct? I added to /boot/armbianEnv.txt and rebooted: (P.S. reboot only works with an external root shell?) overlays=uart3 But opening ttyS3 in cutecom or putty still does not show any incoming data.

Thank you for the Tip! Where i can find the DT overlays? I will check this on the weekend when i am home again ...

Hello, after some time i am trying to work again on my Orange Project. Now i want to connect an serial device on UART2 (PA0 / PA1). The devices /dev/ttyS0 - S3 are existant, but no data is coming in over RXD. I already read the thread here and tried to check the configuration. I upgraded my armbian and i am now working with ARMBIAN 5.60 stable Debian GNU/Linux 9 (stretch) 4.14.70-sunxi64 So i hopefully found the configuration in /boot/dtb-4.14.70-sunxi64/allwinner/sun50i-h5-orangepi-pc2.dtb After decompiling i found uart0@0 { pins = "PA4", "PA5"; function = "uart0"; linux,phandle = <0x23>; phandle = <0x23>; }; uart1 { pins = "PG6", "PG7"; function = "uart1"; linux,phandle = <0x24>; phandle = <0x24>; }; uart2 { pins = "PA0", "PA1"; function = "uart2"; linux,phandle = <0x25>; phandle = <0x25>; }; uart3 { pins = "PA13", "PA14"; function = "uart3"; linux,phandle = <0x55>; phandle = <0x55>; }; The pins should be correct but not for UART0, this should be "PC5", "PC6" I have connected to UART2 and the Pins should work with PA0 and PA1. Any idea why i get no data?

Doesn't it make sense to create additional an shared object file ? With something additional like gcc -shared -fPIC -o libarmbianio.so armbianio.o -lc

Yes - it's clear that WiringPi is not needed for I2C. I added the PC2 board to ArmbianIO: