[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: grub with serial line configuration using PCI serial adapter

From: rishat
Subject: Re: grub with serial line configuration using PCI serial adapter
Date: Tue, 18 Oct 2016 16:10:42 +0300
User-agent: Roundcube Webmail/1.2.0

Yes, I saw this serial card from lspci output. But I haven't found how to display detailed information for certain card. Sooner I'll give you output from lspci -i.

With best regards

On 2016-10-18 14:05, Andrei Borzenkov wrote:
On Tue, Oct 18, 2016 at 12:48 PM, rishat <address@hidden> wrote:
Hi Andrei
May I ask another question? How I can debug this behaviour? I believe that BIOS initializes this adapter. Need to say that "PnP OS" was setted to "Yes"
value. I've changed it to "No" and ... same silence in the minicom.

Well, assuming BIOS did initialize this card it may use different port
address. The one you see in setserial output is assigned by Linux
driver. I do not know how flexible it is, but I presume they may

Try lspci command in GRUB. Does it show your card at all? It also
displays some details of current card setup.

You may want to use "set pager=1" otherwise output will scroll too fast.

If you see your card could you send screenshot of information GRUB shows?

Then I
pulled out this adapter and inserted this pci serial adapter to the other PC computer. It has already integrated COM port, this one is working fine, I
have tried to do serial connection via pci adapter, but again I've got
nothing. I just want to figure out is this something I can do with
motherboard or my pci adapter is not compatible. If I need to change this card do you have list of pci, pci-e card that successfully can by used? Is it possible I've faced to situation when two motherboards can't initialize
this hardware?

Thank you in advance.

Best regards

On 2016-10-18 06:47, Andrei Borzenkov wrote:

17.10.2016 22:22, Songatov Rishat пишет:

Hi thank you for helping me!

Unfortunately I haven't got serial access to the grub after adding this
piece of configuration:

insmod pci
insmod serial
insmod terminal
insmod terminfo

###serial --speed=115200 --port=a880 --word=8 --parity=no --stop=1
serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1

terminal_input serial
terminal_output serial

May be I need some sleep time after inserting pci.mod. How I can do this?

You can pause with "sleep NN" but as I already wrote this is not likely to work anyway - either GRUB needs code to initialize your PCI card or BIOS should do it. Try BIOS settings, in the past it was common to have
something like "PnP OS" where "no" would cause BIOS to initialize all
available hardware and "yes" would leave it to operating system.


Best regards


On 17.10.2016 20:34, Andrei Borzenkov wrote:

17.10.2016 19:41, rishat пишет:

On 2016-10-17 19:16, Andrei Borzenkov wrote:

17.10.2016 16:16, rishat пишет:

setserial -g /dev/ttyS[0-4]
/dev/ttyS0, UART: 16550A, Port: 0xa880, IRQ: 21


When I tried to manually type a "serial --speed=115200 --unit=0
--parity=no --stop=1" in the grub command line it complains that COM1 port don't exist. I have played with unit and port attributes but
without any luck.

Does "serial --port=a880 ..." work? If not, what exactly happens?

Note that you may need to load at least PCI bus driver (insmod pci)
this to work.

I've tried to use it that way but it didn't find com port again.
I'll try to do insmod pci and write to you tomorrow.

Yes, please let us know, but on firther consideration it probably won't
help either. Card likely needs to be initialized first, and this
requires driver that knows how to do it. serial driver in GRUB presumes hardware is in working state already. Someone would need to implement

By the way is it possible to share documentation about some useful
modules in the grub? I havn't found any information using google.

Help-grub mailing list

reply via email to

[Prev in Thread] Current Thread [Next in Thread]