[syslinux] How to press F1 over a serial console?

Richard L. James richard_l_james at yahoo.co.uk
Tue Feb 27 06:03:45 PST 2007


Just realised a problem.  If you have already booted into PXELINUX  etc then you will already be past the point where F1 is still valid since the BIOS only briefly checks for F1 before then going onto other tasks, e.g. booting an OS or a boot loader once that has started the F1 checking has already stopped.

Therefore probably your best bet would be to put in a KVM-over-IP box which will definately let you do this, e.g. http://www.realvnc.com/products/KVM-over-IP/ 

On the subject of PXELINUX it might be theorically possible to do some sort of double boot into PXELINUX and then back to the BIOS routines.  However let's just keep that to a personal theories of mine (well with some testing) as last time I mentioned double booting on this list it seemed to confuse several people and right now I have other things to worry about but I do read this list with interest.

It is also worth flagging that barcode "wedge" scanner adapters are interesting things to play with since many of these devices convert RS232 (from the scanner) to the keyboard TTL connector and also feature a keyboard connector, thus you can plug in one of these adapters to a PC and connect the other up to another PC via a null modem cable to send keyboard commands.  I sadly don't easily have mine to hand to try at the moment and never bothered with trying to send F1 should work....  However this is a separate discussion to PXELINUX etc.
Regards Richard

"Richard L. James" wrote: Hi Ferenc,

Greetings to .HU - to do this you need a way to be able to send the following 2 bytes which represent the keyboard scan code for F1:

1st byte = 0d / 0h / NUL (null character)
2nd byte = 59d / 3Bh / semi column (;)

(see http://www.jimprice.com/jim-asc.htm for more details)

I am NOT personally not that familar with Xterm however this google search returns several pages which should help - http://www.google.com/search?hl=en&q=sending+f1+xterm


Regards Richard

Ferenc Wagner wrote: Hi,

Over a serial emulation provided by the BIOS, I get the PXELINUX  boot
prompt all right.  Now, how do I send F1 to get a help screen?  It's
not PXELINUX specific, of course, F1 would also come helpful for
entering the BIOS Setup program.  Its accross telnet running in an SSH
session from an UTF-8 xterm, as it probably matters.  I would be
grateful for any insight.

SYSLINUX mailing list
Submissions to SYSLINUX at zytor.com
Unsubscribe or set options at:
Please do not send private replies to mailing list traffic.


  New Yahoo! Mail is the ultimate force in competitive emailing. Find out more at the Yahoo! Mail Championships. Plus: play games and win prizes.

 The all-new Yahoo! Mail goes wherever you go - free your email address from your Internet provider.

More information about the Syslinux mailing list