[SOLVED] apu2 internal TTL com port

doktornotor

That's not the problem. The problem is that COM1 is hardcoded in the boot blocks. Changing it on the fly is not possible. See the linked howto.

jimp

You can install using the ADI image to get a serial console on COM2 but I'm not sure what other side effects you might have with that image on non-ADI hardware.

xbipin

Thanks for the info, btw I found one method to get serial console on com2 so I'll get time to test it on Saturday and report back if it works, the other reason I want this to work is for a remote site where they only have a USB to ttl adapter which can connect to com2 and traffic shaping is crashing their system so need to get a crash dump because the system isn't saving it and keeps rebooting

stephenw10

I have found that nothing more is required than adding to /boot/loader.conf.local

comconsole_port="0x2F8"

You may not get the full boot output from that but you should get the console/menu.

Steve

xbipin

Exactly the same stuff I read in a Reddit post and wanted to try, don't want the boot output, just want the console menu and afterwards

xbipin

@stephenw10:

I have found that nothing more is required than adding to /boot/loader.conf.local
comconsole_port="0x2F8"
You may not get the full boot output from that but you should get the console/menu.

Steve

i tried this and it works but i have another issue which i was coordinating with pcengine guys and came to the conclusion that when we redirect serial console to com2 header on apu2 using the above in loader.conf.local then console stops and the com1 and it get silent so thats fine but then the com2 starts giving the console along with a constant stream of garbage which never stops, at first i was told my usb to uart adapter might be faulty so tried a different chipset one and its same and also tried on 2 apu2 boards and it same so any idea why is pfsense or freebsd doing this?

stephenw10

What is it actually sending to the port?

Steve

jimp

"garbage" makes me think it's sending at a different serial speed, whatever it is. Doesn't sound like anything that pfSense or FreeBSD would be doing though.

xbipin

from time to time i see valid serial output but then it comes along with lot of garbage characters non stop, i tried the default baud rate of 115200 as well as all possible baud rates and its same except on other baud rates its total garbage, atleast on 115200 i see some of the pfsense output but the garbage is so much that it comes in bits and pieces.

stephenw10

A bad connection or interference on the cable can appear like that. Is the cable particularly long?

Steve

xbipin

no its hardly 15cm and plus its happening on my adapter and apu2 as well as a different one in a client location.

stephenw10

Do you see that even when the console has not been switched to it?

Steve

xbipin

yes but only when i press enter then all the garbage starts non stop, on a fresh boot when i connect doesnt display anything.

stephenw10

Hmm, sure sounds like something else is using the port. Just because the output is not ASCII does not mean it's garbage though, it may be some other format.

Are you sure you haven't configured anything else on that port? Do you see that output even if pfSense it not booted?

Try looking at the raw serial output rather than using a terminal emulator. That will rely on the port settings being correct.

Steve

xbipin

when pfsense is not booted its blank coz the apu2 sends its bios menu only to the com1 which is the serial port, i have nothing else configured just a basic pfsense firewall with mostly everything default.

i dont understand what do u mean by "Try looking at the raw serial output rather than using a terminal emulator. That will rely on the port settings being correct."

stephenw10

Ok, and hitting enter at that point does not start a stream of unreadable characters?

That implies it's something being loaded by pfSense rather than debug output from the CPU or whatever.

Are you sure you don't have say lcdproc or nut loaded?

You are looking at the serial output with a terminal emulator that tries to interpret the data as characters or instructions to move the cursor etc but not all serial data is that.

Try running on the connected device, for example:

cat /dev/(your usb serial port) > /tmp/serial_output

Then open that file in a hex editor. Since you can;t set the port speed it replies on whatever the port settings are already set to which must be correct to see meaningful data.

Moving this to hardware since it's not 2.4 related.

Steve

xbipin

no i dont have lcdproc or nut loaded, give me a few days as i have ordered a few more usb to uart adapters so once they arrive can attach those and test as well and report back as well as pcengines ppl are also testing it on their end to see if its debug info or no

stephenw10

I only suggested debug output there because the ALIX had this diagram available which is labelled debug so it seems to be something they might have done previously. A lot of speculation there!
However if it were I might expect to see it whether or not pfSense loaded.

Steve

xbipin

pcengines ppl just tested it using the same usb to ttl adapter and they send me a screenshot of it working and displaying properly so now im wondering if my tera term app is faulty or no so trying with putty

xbipin

i tried with putty and its still same so lets just wait for the other adapter to come then ill report back