Enable the serial port in Debian Jessie

xwalter

Hello eveyone !Does someone can help me to solve the problem of serial port /dev/ttyS0 ?
It seems that I have to open some files and set something to use the serial port .....
Thanks !

xwalter

at the moment in the /etc/inittab I have this information
S0:23:respawn:/sbin/getty -L ttyS0 115200 vt102Measuring with Voltmeter I have
GPIO14 - GND = 3.3 V
GPIO15 - GND = 3.3 V
The GND of orangepi is connected to GND of FTL232-USB to TTL 3V3 converter
It seems that the two pins are setted as output ...I don't know
I hope the layout pins is correct because I didn't found an orangepi pinout diagram but raspberry pi2

xwalter

I did some tests

1. setserial -g /dev/ttyS[0123]

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this is ok ....and then I set the serial ports enabled

1. systemctl enable serial-getty@ttyS0.service

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To check is serial port are enabled I see the IRQ assigned and it's ok
Then I type

1. dmesg | grep ttyS

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Ant last control is

1. ls > /dev/ttyS0

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1. ls > /dev/ttyS2

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1. ls > /dev/ttyS3

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Without any message and it's ok
But the serial ports don't work , no one port receive something and transmit something
This is a big problem ....

WereCatf

Do you actually have those serial-ports enabled in your script.bin?

xwalter

in /boot  I have several script.bin , each one for each monitor resolution
Very strange because when I prepared the sd card I have followed the tutorial and renamed the uImage and script.bin depending by my monitor
But anyway inside the script.bin_xxxxx  I can read only one character which is  "N" in somewhere and "0" in other file
I have setted 1080_60 for the monitor  .....I have orangepi plus 2 and inside /boot I found two files for that ....
- script.bin.OPIPLUS_1080p50
- script.bin.OPIPLUS_1080p60
In both files there is only one data and it is 0  (zero) , but when I have installed from sd card was 36 kb ...then I install to the emmc by typing sudo install_to_emmc.
Do you mean I have to set to 2 or 3 to have uarts?
One question.....at pins 13 and 14 there is uart3 = /dev/ttyS3 ?

xwalter

I'm checking into my sd card that I remained with last image and script.bin but how to open it ?

WereCatf

You need to install sunxi-tools, then you convert the bin-file to a fex with "bin2fex script.bin > script.fex" or back with "fex2bin script.fex > script.bin"

Depending on your distro the actual files used for booting may be in /mnt/boot or /media/boot, even though there are also files in /boot.

xwalter

ok thanks !
Now I try to install sunxi-tools

fritz

/dev//ttyS0 is the debug port! Attach your serial dongle there and you will see something.
check sunxi wiki!
e.g. http://linux-sunxi.org/Xunlong_Orange_Pi_Plus should be the same for pi plus2 apart 2gb ram same crappy usb to sata.
zio pino

xwalter

yes you're righe zio pino . The orange pi plus is the same of plus 2 apart the EMMC and  the RAM sizes.
At the moment I have connected the pins PA13 and PA14 each which is :
- PA13  ->  UART3_TX
- PA14  ->  UART3_RX
So I'm using the /dev/ttyS3  ,  is that right?
Yes because ....

1. dmesg | grep ttyS

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Responds .....

1. [    0.000000] Kernel command line: earlyprintk=ttyS0,115200 loglevel=8 initcall_debug=0 console=ttyS0,115200 console=tty0 init=/init
   
2. [    0.627413] uart0: ttyS0 at MMIO 0x1c28000 (irq = 32) is a SUNXI
   
3. [    0.723616] console [ttyS0] enabled
   
4. [    0.850323] uart2: ttyS2 at MMIO 0x1c28800 (irq = 34) is a SUNXI
   
5. [    0.850572] uart3: ttyS3 at MMIO 0x1c28c00 (irq = 35) is a SUNXI
   
6. [   10.213707] systemd[1]: Expecting device dev-ttyS0.device...
   
7. [   10.228992] systemd[1]: Expecting device dev-ttyS3.device...
   
8. [   10.244060] systemd[1]: Expecting device dev-ttyS2.device...
   

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The test

1. ls > /dev/ttyS3

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....it's ok , no message
But serial doesn't work yet