serial debugging - dumb question

Andrew Atrens atrens at nortelnetworks.com
Thu Apr 8 11:57:22 PDT 2004


Hi Folks,

I guess I should apologize first before you read any further, for the 
dumbness of this question ....


I've got a few 4.x systems kicking around, and at the moment have one hooked
via serial port to my dragonfly box. I was hoping to use it to help debug
some lockups I'm seeing...

Not sure if this is possible or if I'd need to convert it to DragonFly
first...

On the Dragonfly box I break to ddb, and type 'gdb' and then 'c' to
continue. Then I break to ddb again and it tells me that it's received
the break and I assume is now chatting on the serial port ...

On the 4.x (4.10beta) box, I see -

$ gdb -k
GNU gdb 4.18 (FreeBSD)
Copyright 1998 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-unknown-freebsd".
(kgdb) target remote /dev/cuaa0
Remote debugging using /dev/cuaa0
Ignoring packet error, continuing...

Ignoring packet error, continuing...
Ignoring packet error, continuing...
Couldn't establish connection to remote target
Malformed response to offset query, timeout
(kgdb)
(kgdb) quit

Not sure if I should be using the ttyd0 instead of cuaa0, or perhaps 
something else entirely different?

Not 100% sure about my cable either, I just grabbed it out of a big box
of random cables in our lab ... It *looks* like a good cable.

Could I perhaps also be using the wrong baud rate ?

Any help our pointers to help would be greatly appreciated ..

Cheers,

Andrew.









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