Mity CPU Platforms » MitySOM-5CSX Altera Cyclone V

Hello,

Hi,

I am working on enabling Jumbo Frames and need to increase the MTU size on the eth0, eth1, and br0 interfaces. While I was able to successfully update the MTU size for eth1 and br0, I encountered an issue with eth0. When attempting to bring the eth0 link down to modify its MTU size, the link is automatically brought back up, preventing me from making the change. Could you please advise on how to address this issue?

Hello,

It might be that you need to take br0 down before taking eth0 down. The issue could be that br0 isn't allowing eth0 to go down.

Dan

Hi,

yeah i'm tried that firstly i am down the br0 and its goes to down then after i am tried to down eth0, its going down properly but it automatically brings up, it was not able to bring down eth0.
please find the below screenshot.

Hi,

I was able to recreate the issue on a board here. The ifplugd service, which is used to detect ethernet connectivity status, is bringing eth0 up as soon as you bring it down. You need to stop the ifplugd service before bringing eth0 down.

Here is the commands I ran:

root@mitysom-c5:~# /etc/init.d/ifplugd stop
Stopping Network Interface Plugging Daemon: eth0.
root@mitysom-c5:~# ip link set br0 down
root@mitysom-c5:~# ip link set eth0 down 

Hi,

MTU size issue was Resolved, and now I am facing with Crontab.
Actually I am running an application code on boot time and that way I am added the Executable lines on crontab. I am facing an issue with that after booting, my code has been executed properly, but in UART its transmits data properly but not receiving the data. when i am running my application code normally in terminal after booting the HPS, it was working fine, but the issues was coming when the application code was running through crontab.

If your program is reading from standard input, it will not be able to read anything when launched from cron. cron jobs have their standard input closed (or set to /dev/null, I don't remember exactly) and standard out will be shown in the console. I am guessing that the UART you are referring to is the console serial port?
You cannot run an interactive application from cron and using the console port as anything other than the console is really not a good idea..
If you are talking about a different UART that your application has opened and configured itself, then something else is going on.

Hi,

I am currently working with the MitySOM Cyclone V device, which has only a single UART port. During boot-up, the boot logs are coming through this UART port. Once the system finishes booting, it prompts for a login. I am manually log in by entering "root" without any password. After logging in, I am able to run my application code manually, and the UART port functions correctly, both sending and receiving data as expected.

However, when I attempt to run the same application through crontab, the application executes, and the MitySOM board is able to transmit data but MitySOM does not receive any data on the UART port. The issue seems to occur only when the application is run through crontab, whereas it functions properly when run manually.

Hello,

As Tim said an application launched through cron won't have access to standard in and out. What you could do is have getty(the login manager) autologin as root and use a .profile config file to launch your application.

Here is the updated needed to /bin/start_getty to auto login in as root:

- ${setsid:-} ${getty} -L $1 $2 $3
+ ${setsid:-} ${getty} --autologin root -L $1 $2 $3

/bin/echo "Hello" 
/usr/bin/bc

What Dan showed you will start your application in the console... if your application exits (or you kill it with ctrl-c) you will be dropped to the command line, where you can restart your application or do other things.