Next: Adding a new board, Previous: Adding a new tool, Up: Extending DejaGnu
DejaGnu has some additional requirements for target support, beyond the
general-purpose provisions of a configure
script. DejaGnu must
actively communicate with the target, rather than simply generating or
managing code for the target architecture. Therefore, each tool
requires an initialization module for each target. For new targets, you
must supply a few Tcl procedures to adapt DejaGnu to the target.
Usually the best way to write a new initialization module is to edit an
existing initialization module; some trial and error will be
required. If necessary, you can use the --debug
option to see
what is really going on.
When you code an initialization module, be generous in printing
information using the verbose
procedure. In cross-development
environments, most of the work is in getting the communications
right. Code for communicating via TCP/IP networks or serial lines is
available in a DejaGnu library files such as lib/telnet.exp.
If you suspect a communication problem, try running the connection
interactively from Expect. (There are three ways of running Expect as
an interactive interpreter. You can run Expect with no arguments, and
control it completely interactively; or you can use expect -i
together with other command-line options and arguments; or you can run
the command interpreter
from any Expect procedure. Use
return
to get back to the calling procedure (if any), or
return -tcl
to make the calling procedure itself return to its
caller; use exit
or end-of-file to leave Expect altogether.) Run
the program whose name is recorded in $connectmode
, with the
arguments in $targetname
, to establish a connection. You should
at least be able to get a prompt from any target that is physically
connected.
Next: Adding a new board, Previous: Adding a new tool, Up: Extending DejaGnu