/etc/inittab no longer present in Raspbian Jessie?

[greatislander]

Just installed Jessie on my Raspberry Pi Model B, and I went to edit /etc/inittab to configure my serial interface—and it's not there. What's the story?

[ShiftPlusOne]

inittab was a part of sysvinit, which has been replaced with systemd.. Serial getty is now a service like any other. What would you like to do exactly?

[engineer_m]

I also have this problem. Previously i used sudo wget https://raw.github.com/lurch/rpi-serial ... al-console -O /usr/bin/rpi-serial-console && sudo chmod +x /usr/bin/rpi-serial-console.With that script I enabled and disabled my serial console, and i also changed its baud rate. How can i do that now?

[ultrademon666]

Hi, i also had the same problem:

You have to disable the serial getty service:

Code: Select all

sudo systemctl stop [email protected]

you can also disable it from start again:

Code: Select all

sudo systemctl disable [email protected]

[engineer_m]

can you please tell me how to change the baud rate?

[tlc]

Hello.
The same question - Can anyone tell how to change baudrate for [email protected]
I do not want to have kernel messages on ttyAMA0, but I want to have serial terminal connected via ttyAMA0 with 9600kbit speed.
Thanks
Tomas

[diederik]

I do not want to have kernel messages on ttyAMA0, but I want to have serial terminal connected via ttyAMA0 with 9600kbit speed.

Modify /boot/cmdline.txt so it has sth like this:

Code: Select all

console=ttyAMA0,9600 kgdboc=ttyAMA0,9600 console=tty1

By having tty1 as the last console it will receive the kernel messages and not ttyAMA0

[tlc]

Thanks diederik.
But this does not work in Raspbian Jessie with systemd.
I have already tried some combinations like
console=ttyAMA0,9600 kgdboc=ttyAMA0,9600 console=tty1
console=ttyAMA0,9600 kgdboc=tty1 console=tty1

But kernel messages are still on both tty1 and ttyAMA0

Tomas

[tlc]

I have made next set of searches...
Tried sugestion on http://archlinuxarm.org/forum/viewtopic.php?f=31&t=5640 - just to make link

Code: Select all

ln -s /lib/systemd/system/[email protected] /etc/systemd/system/getty.target.wants/[email protected]

and erase ttyAMA0 from cmdline.txt - and it works ok for me now.
It seems that agetty is started with capability to support three speeds by default:
ExecStart=-/sbin/agetty --keep-baud 115200,38400,9600 %I $TERM

Tomas

[diederik]

Thanks for reporting the solution back, much appreciated

[vilo]

Under Raspbian Jessie, you can use:

Code: Select all

sudo raspbian-config

Then choose "Advanced Options", then "Serial" and answer "No" to the question "Would you like a login shell to be accessible over serial?" However, this also removes the /dev/ttyAMA0 device.

[barthawk]

Is there a way to get /dev/ttyAMA0 back if we disable serial consoles in raspi-config?

[ShiftPlusOne]

enable_uart=1 in config.txt ensures the hardware itself is registered by the kernel.

[barthawk]

Thanks for the suggestion, I checked the config.txt file and enable_uart=1 was already in the file, but there is still no /dev/ttyAMA0 file when I boot.

I'm, trying to write from a python script to the serial port. On my Pi Zero, the cmdline.txt doesn't refer to ttyAMA0, but serial0 which is linked to ttyAMA0. I remove that bit from cmdline.txt, but then when I reboot //dev/ttyAMA0 don't exist. If I tried the linking as described above, then I get a single message on the serial port saying "Uncompressing Linux... done, booting the kernel" but no logon prompt. Then /dev/ttyAMA0 exists.

However, when I try to open the port using python I get the message saying "Port is already open".

EDIT *User Error*
I didn't realize that defining the serial port in python opened the port automatically and I tried to open the port again, resulting in the error. It does appear that just removing the references to ttyAMA0 or ttySerial0 in the /boot/cmdline.txt while enabling the use of the serial port using raspi-config will enable the use of the serial port from user land programs. I did also change the permissions on ttyAMA0 to +0666 to allow regular users to write to it.

Thanks

[netdudeuk]

Hi

I have the same issue.

My cmdline.txt looks like this -

dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

It used to look like this -

dwc_otg.lpm_enable=0 console=tty1 console=serial0,115200 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

I can access the serial port from Python but I still get the same "Uncompressing Linux... done, booting the kernel" message in the terminal window. What is needed to disable this message ?

Thanks

[nadeto9696]

Hello,

I am trying to connect a Pi-Lite to a Pi 2B. I followed the instructions available and found out that the inittab file has been replaced with another one. However I couldn't find instructions anywhere about how to procede with the new os.

Can anyone help?
Cheers.

[DougieLawson]

Hello,

I am trying to connect a Pi-Lite to a Pi 2B. I followed the instructions available and found out that the inittab file has been replaced with another one. However I couldn't find instructions anywhere about how to procede with the new os.

Can anyone help?
Cheers.

Can you post a link to the historic instructions you're following? What is it doing to inittab? If it is just to disable the serial console then there's an option in sudo raspi-config to do that for you on Jessie.

[danpeirce]

Thanks for the suggestion, I checked the config.txt file and enable_uart=1 was already in the file, but there is still no /dev/ttyAMA0 file when I boot.

I'm, trying to write from a python script to the serial port. On my Pi Zero, the cmdline.txt doesn't refer to ttyAMA0, but serial0 which is linked to ttyAMA0. I remove that bit from cmdline.txt, but then when I reboot //dev/ttyAMA0 don't exist. If I tried the linking as described above, then I get a single message on the serial port saying "Uncompressing Linux... done, booting the kernel" but no logon prompt. Then /dev/ttyAMA0 exists.

However, when I try to open the port using python I get the message saying "Port is already open".

EDIT *User Error*
I didn't realize that defining the serial port in python opened the port automatically and I tried to open the port again, resulting in the error. It does appear that just removing the references to ttyAMA0 or ttySerial0 in the /boot/cmdline.txt while enabling the use of the serial port using raspi-config will enable the use of the serial port from user land programs. I did also change the permissions on ttyAMA0 to +0666 to allow regular users to write to it.

Thanks

Yes that (bold) seems to have worked for me using the Raspberry Pi Zero. In this case it was a reference to ttySerial0 that I removed.
As someone pointed out I am getting a message on ttyAMA0 on a reboot:

"Uncompressing Linux... done, booting the kernel. "

But since I will be writing custom firmware for the device I'll be connecting to the RPi zero that message could be handy. My PIC32 will boot faster and will need to wait for the RPi zero to come up.

[nadeto9696]

Hello,

I am trying to connect a Pi-Lite to a Pi 2B. I followed the instructions available and found out that the inittab file has been replaced with another one. However I couldn't find instructions anywhere about how to procede with the new os.

Can anyone help?
Cheers.

Can you post a link to the historic instructions you're following? What is it doing to inittab? If it is just to disable the serial console then there's an option in sudo raspi-config to do that for you on Jessie.

Hello again and thanks for your reply!

I managed to disable the serial port through the raspi-config menu but now I am struggling with disabling the bootup info on the serial port and using the minicom. I am following this guide: http://www.raspberrypi-spy.co.uk/2013/0 ... rix-board/ . When I execute the command sudo nano /boot/cmdline.txt I get something really similar to the expected sentence: dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p7 rootfstype=ext4 elevator=deadline rootwait. Should I change it to the expected sentence or is it just changed for this version of the Pi/OS? The next step - the minicom is also not working, supposedly because I am not sure if the disable of the bootup step is fine. The line minicom -b 9600 -o -D /dev/ttyAMA0 is not doing anything for me. (''pressing keys on your keyboard should result in them appearing on the Pi-Lite!'')
Basically I am very confused and have little to no idea about what is going on. Any help is appreciated.

[DougieLawson]

Stop using an OUT OF DATE article from 2013. Find something that's current.

Also it's against the forum rules to post multiple topics on the same subject. Keep everything in one thread.

[charlzmon]

This should sort you out
https://spellfoundry.com/2016/05/29/con ... ding-pi-3/

I was struggling with the same thing: using outdated tutorials.

[klampth]

That is my configuration (i'm using Berryboot):
###Com port ###

sudo systemctl stop [email protected]
sudo systemctl disable [email protected]
sudo chmod a+rw /dev/ttyAMA0

nano /boot/cmdline.txt

elevator=deadline quiet bootmenutimeout=10 datadev=mmcblk0p2 console=ttyAMA0,115200 console=tty1

ln -s /lib/systemd/system/[email protected] /etc/systemd/system/getty.target.wants/[email protected]

sudo systemctl enable [email protected]
sudo systemctl stop [email protected]

reboot

### GPIO setup ###

GND - GND
TX - RX
RX - TX

### Using minicom ###

sudo apt-get install minicom
minicom -b 115200 -o -D /dev/ttyAMA0

[PianoPCJ/A.F]

Hello,

I almost have the same problem. I will explain my situation: I have a Raspberry Pi 3 Model B and I want to edit the inittab.txt file but it does not exists . In a tutorial to build a Midi-synth they used an Raspberry 2 but I thought there are no differences between the Raspi 2 and Raspi 3... and here I red that this file was replaced by another file.
In the tutorial it says:
"Next, edit the cmdline.txt and inittab.txt to disable accessing the Pi's shell from UART (leaving it open for MIDI access). Make a copy of each file..."
the comand to copy it:
sudo cp /etc/inittab.txt /etc/inittab.bak

and the comand to open( and edit) it:
sudo nano /etc/inittab.txt

the tutorial you can find here:
http://www.instructables.com/id/PiMiDi- ... earned-to/

can you alp me?
bye

[ShiftPlusOne]

Use raspi-config to disable serial shell instead of the way they say in the tutorial. You want to keep the hardware enabled, but disable the shell (it should ask you two questions).

[PianoPCJ/A.F]

Use raspi-config to disable serial shell instead of the way they say in the tutorial. You want to keep the hardware enabled, but disable the shell (it should ask you two questions).

what do you mean with raspi-config? is this a comand or a file?